June 28, 2017


Going on the offense...Or, is that defense?

I wanted to continue a bit on the discussion we had yesterday about managing our aquariums in a manner which mimics natural processes. Specifically, I wanted to talk about practices which create great long-term outcomes for our aquariums. Proactive stuff.

It involves looking at our aquariums from multiple perspectives.

You've heard the time-worn sports cliches and how they apply to other areas of life...and they apply to aquarium-keeping for sure:

"The best offense is a good defense."

"Offense scores points. Defense wins games."

Well, they do. Which one is most applicable?

Both. Applied in the proper measure. At least, that's my take on it.

We need to play "defense" in our fish-keeping as much as we play offense.

"Defense", in our world, is the day-to-day things that we need to do to keep our tanks running well: Feeding fishes, observing, adjusting parameters to make sure that the system is running optimally, or reacting to a disease or other health issue of the fishes and plants, or repairing equipment, etc. "Defense", in this context, is what almost every aquarist on the planet practices on a daily basis.

Would we be better served buy investing more energy in offense? You know, "attacking" problems proactively from the outset? Before they become problems? I think so. It's one thing I can say was a positive gain from reef keeping: Setting up a system from the start to address the potential "what-ifs?" Reefers are really good at this sort of stuff (just look at the gadgetry and plumbing in some of those forum "tank-build threads!"), and it translates well to freshwater.

Although I've typically been a "Don't f - - - with- the- tank- once- it's- up- and- running"- kind of aquarist for many years, my philosophy has evolved a bit since I began working heavily with botanical-influenced systems. The offense-defense dynamic is more important that ever.

An example of "offense", in this context, would be setting up a new system to create an optimal environment to breed your fish. Things that are big-picture, growth activities are also "offensive." You know, selecting the proper sized aquarium, appropriate filter, heater, and other components falls into this category. In a botanical-style aquarium, much like any other, it's important to create the optimum situation to assure that the system can function properly as it evolves over time. A mix of "defense", with a healthy dose of "offense." 

"Offense" also includes things like stocking the tank with a mix of appropriate fishes, which are compatible and capable of serving in the environment which you've created. Making logical decisions is an essential part of the development of any aquarium, although in a blackwater/botanical-style aquarium, you need to take into account the other variables in the equation: Lower pH, the bioload of decomposing botanical materials, and the long-term maintenance of stable pH and organic levels. We've talked repeatedly about not obsessing over target numbers, yet the importance of maintaining a tight range for most parameters cannot be understated.

What other "offensive" things can you do to assure long-term success in a blackwater, botanical-style aquarium?

We've mentioned many of them repeatedly here over the past couple of years; most are sort of automatic" to many of us now. Yet, in my opinion, there is one practice that stands out above all others in the context of our approach:

The continuous replacement and supplementation of leaves and botanicals as they start to break down. This not only creates a continuously evolving aesthetic, it helps maintain the biological diversity and environmental parameters are held in the cherished "tight range".

I know a few "tinters" who make significant replacements of leaf and botanical items and replace them with fresh materials simultaneously, and this is conducted on a regular basis. This is similar to the Japanese aquascaping practice of "sozo haishoku" espoused by Takashi Amano, which is the processs of removing of as much old substrate material as possible along with the plants it contains in an aquarium, and replacing them with new materials. It preserves the overall "composition" of the layout, but the "softscape" (botanicals and leaves, in our case) could change dramatically.

This process is very interesting to us as botanical-style aquarium fans, because, as we talked about yesterday,  it does sort of mimic what happens in many streams and rivers on a seasonal basis: Older materials are swept downstream as the watercourses swell, and are replaced by new ones that arrive to replace them. And of course, in the aquarium, performing a "sozo haishoku"-type replacement of materials can significantly change the aesthetic of the aquascape because the botanicals are replaced with different ones after the previous ones are removed.

Now, personally- I'm a fan of less "radical" moves, and in the interest of a good "offense", I favor regular additions to the botanical "set" in my aquariums. I tend not to remove any decomposing botanical material, unless it becomes an aesthetic detraction because it's blowing all over the place or something like that. Having studied many images of Amazonian igarapes, it is very obvious that, although some materials are swept away, many remain in place until they fully decompose, adding to the richness and complexity of the habitat, and that we can mimic this process in our aquariums to some advantage.


And defense.

Working together for long term success. It's a beautiful dynamic. A beautiful game.

Massage it. Evolve it. Tweak it. Perfect it, if you can.

Stay on top of stuff. Stay observant. Stay vigilant. Stay cautious. Stay bold. Stay balanced.

And Stay Wet.

Scott Fellman

Tannin Aquatics


June 27, 2017


Rain, predators, pools...and "riffles": The dynamics of natural processes and the benefits of mimicking them in our aquariums

Wow- perhaps the longest blog title of the year to date, huh? Don't worry, it's a relatively simple thought, despite it's voluminous size...

Those of you who regularly read this column know that I like to reflect frequently on the "process" of evolving and changing aquariums over time. I view every interaction with our tanks as an opportunity to reflect, observe, and manage the long-term evolution of them.

Thursdays are  water exchange days for our office aquariums. And, rather than look at it as some task on a checklist of stuff to do, some necessary evil" chore- we regard them as... opportunities.

A water exchange represents an opportunity to refresh, reinvigorate, and interact with the aquarium on a much more detailed, intimate level. We've pointed out many times before that, in a blackwater/botanical-style aquarium, the regular water exchanges we conduct on our aquariums are, in many ways, very much a mimicry of what happens in the wild streams and rivers of the tropical world during the rainy season: New water is added to the environment, old botanical materials and leaves are swept away from their current locations, and a new set of materials are deposited in their place. More so than perhaps other types of aquariums- the practice of replacing botanicals and leaves along with new water is a significant "weekly evolution" of the environment in this style of system.

Beyond a simple "editing ritual" or an aesthetic "refresh", this is a very dynamic process, yet one which also provides longer-term benefits for the ecosystem, because, as these newer materials are deposited, they not only help "reinforce" the matrix of botanicals already in place, they provide new "structure", new foraging, new chemical inputs (like tannins and other organics), and provide fresh material for the continued development of food webs, starting with microbial life and fungi, to algae, and on up to insects and crustaceans, which form the "backbone" of the diet of many of our fishes which hail from these habitats.

In nature, the rain also effects the depth and flow rates of many of the waters in this region, with the associated impacts mentioned above, as well as their influence on stream structures, like submerged logs, sandbars, rocks, etc. Much in the way we might move a few things around now and again during maintenance!

And stuff certainly gets moved around, re-distributed, and otherwise affected in the wild as a result of rain!

For example, seasonal water levels can rise up to 20 meters (65 feet) in the middle Amazon region! That's a lot of water! Towards the mouth of the Amazon, the yearly change becomes less and less, but even near  the Rio Xingu, it can still be as much as 4 meters (12 feet). This seasonal deluge has huge impact on not only the physical structure of the associated rivers, streams, and their surrounding forest terrain, but on the fishes and other creatures which reside in them.

Amazonian streams typically feature two interesting biotopes that we haven't really discussed in much detail here, and both of which are quite profoundly impacted by the seasonal rains: Pools, with slower current and a substrate covered mainly by deposits of leaf litter, detritus and driftwood; and "riffles' (defined as shallow sections of a stream with rapid current and a surface broken by gravel, rubble or boulders), with a moderately-fast-flowing current and mostly sandy bottom with tree roots, driftwood pieces, and small rocks and pebbles. (ohh...home to Darter Characins!) These riffles are considerably more significant in the wet season, when the obvious impact of higher water volumes are present.
And interestingly, you'll find an unexpected abundance of some species familiar to us as hobbyists in these riffles. Species like Pyrrhulina brevis, Hyphessobrycon melazonatus, and Hemigrammus of various forms, and even some Nanostimus marginatus and the killie Rivulus compressus! I find this intriguing, because we tend to associate a lot of these little fishes with sluggish water and more static environments, not areas exposed to greater current and movement. 
I pose the question once again (which we sort of hashed out on Facebook last week):
Do we need to consider applying larger volumes of "intelligent" water movement to our typical freshwater aquariums? I believe that the answer might be a resounding yes, and point to the observations about the physical habitats above as a model.
Oh, back to those Amazonian pools...
Interesting "factoid": Some scientists have postulated that the higher presence of nocturnal predators in the pools might increase the number of species that seek refuge in the riffles to avoid them! And Rivulus, which usually live in more intermittent pools along the stream edges, outside the main stream channels, are normally found at night in these riffles!  
This makes a lot of sense, right? I mean, it's a lot harder to catch your dinner when you have to contend not with the current as well! Quite a defensive mechanism!
(pic by Clinton and Charles Robertson under CC BY 2.0)
How can we as hobbyists use these kinds of pieces of information to create more realistic closed ecosystems for our fishes?
At the very least, I think it important to continue looking at our water exchanges and botanical additions/removals in the context of how natural bodies of water actually function. Such a point of view will keep our minds open and senses attuned to the evolving habitat within that glass or acrylic box which our fishes call home.
Change in these habitats is constant. Adaptation by our animals to them is as well.
Interesting stuff to ponder, isn't it?
Stay observant. Stay curious. Stay contextual. Stay excited.
And Stay Wet.
Scott Fellman
Tannin Aquaitcs 
June 26, 2017


The "why's and hows" of mangrove wood in the brackish water/botanical-style approach...

Yes, it's Summer, we're out doing other stuff, and we're really a couple of months away from prime "aquarium season", yet it's always a good idea to start thinking about some of the cool projects we want to play with during the upcoming cooler months of Fall. And, if you're looking for something new to play with when you head back indoors, may we suggest a brackish water aquarium? Or, our version of a brackish-water aquarium?

Our vision of a brackish water aquarium utilizes many elements common to other aquascaping approaches and aquarium environmental management methods. Although we are taking a sort of different route and philosophy in regards to the functionality (mainly, creating a rather "rich system" from an ecological standpoint), the concept is not that much different from what we've been working with in blackwater. It's just that greater emphasis is placed on the specific components in the system.

One of the most obvious differences (besides the salt, of course!) is the use of a different type of wood than we're used to. We utilize the branches and roots of the Red Mangrove tree (Rhizophora mangle), because, well- they're the "real deal", and we have a legally-collected source for them. 

Mangrove wood imparts many of the same properties to the water as any other type of wood used in aquarium setups. It will slowly release tannins, which may tint the water, and recruit biofilms and algae. The main difference between our approach to utilize mangrove versus any other wood is that it looks like the real thing because it IS the real thing.

And the actual mangrove wood is different than wood or branched from other trees that might be used in aquarium work. For one thing, it's structurally different. Red Mangroves prop themselves above the water level with stilt roots and can then absorb air through pores in their bark. Red mangroves eliminate salt through very impermeable roots which incorporate a waxy substance called suberin. Its main function is as a barrier to movement of water and soluble substances within the tree itself. In the case of the Mangrove, the suberin is used as a sort of filtration mechanism to export sodium salts from the rest of the tree. It's really efficient, too. Scientists have discovered that up to 97% of the salt has been removed from the tree via the root! This is very special wood!

Mangroves grow in muddy substrates which have little free oxygen available. Anerobic bacteria present in these substrates liberate nitrogen and other compounds that are present, leaving it rather devoid of many substances plants need for growth.  The aerial roots of mangrove trees (known as "pneumatophores", allow then to absorb gasses directly from the atmosphere, and to derive some nutrition from the relatively non-nutritious soil. These trees are also able to store atmospheric gasses within the roots, processing them at all times (submerged or not).

These are extremely adaptable trees, and are thought to be major buffers against the tidal actions of cyclones, tsunamis, and other storms. They foster a diversity of animal life, and for the basis for a unique and fascinating habitat.

With so much usefulness it's hardly surprising that these are highly valued in many parts of the word, and are, indeed, protected in many of them. In fact, you might ask how we in all good conscience can offer the wood for sale! The answer is as surprising as it is legitimate. The only reason we are able to legally offer this wood is because our source is from the State of Hawaii, where the local government has declared the species to be "highly invasive", damaging the local ecosystem, and extensive eradication efforts are continuous. Red mangroves in Hawaii have been found to grow to higher densities than in their native range, because Hawaii lacks the species that attack the flowers and propagules. They grow uncontested; out of control, causing problems for the local flora and fauna. Removal is important.

And it's not just the growth that's problematic- it's the leaves they drop. Beneficial in ecosystems that are "equipped" by nature to accommodate it, the leaves are extremely problematic in Hawaii. The amount of "litter-fall" from mangrove stands at Nu‘upia Pond, Oahu, for example, has been measured at levels which exceed the "net primary productivity"  of the Red Mangrove tree in its native range in Florida  These added organic inputs have led to detrital accumulations and algal blooms in Hawaiian waters, negatively impacting aquatic life.

Surprising, huh?

The local authorities and the U.S. Department of Agriculture are happy to see us take them off of their hands! So, in a strange twist of irony, you're actually helping the local Hawaiian ecosystem and the government to a certain extent by purchasing this mangrove wood from us. And, as an added bonus, you're utilizing the branches and roots- which would otherwise be chain-sawed down and burned- for aquarium decoration, sparing the need to use other methods to dispose of the material. And you could argue that gas-powered chain-saws, and bulldozers and burning them releases carbons into the atmosphere which can contribute to global warming, etc., so I suppose one could make a (weak) argument that taking a tiny, tiny fraction of them for aquarium use is sort of doing something to combat this!

Yup, strangely ironic, regardless, right?

So how do you use mangrove wood in the aquarium? Well, really, just like any other type of wood, really.  Preparation is just like any other wood we all use. The main differences when using mangrove are the context and the physical orientation. The context being, we're using them in an aquarium that has a specific gravity of around 1.003-1.005, and that we're okay with it releasing some tannins into the water and creating some tint. It's as much an "environmental enrichment vehicle" as it is an aquascaping "prop" for us. It beautifully replicates the look of the habitat, while providing some functional benefits (i.e.; a substrate for organisms, plants and algae to attach to and hide amongst).

From an "orientation" standpoint, to get maximum functionality and realism out of the wood, you would be best served to orient it vertically in the aquarium, as opposed to horizontally or in some other configuration as we do with other wood. In particular, the mangrove branches that we offer are essentially identical to the appearance of the prop roots that project downwards from the mangrove trees into the water. By orienting the branches this way, and supplementing them with the thicker, more gnarled mangrove root pieces, you'll end up with an incredibly realistic-looking simulation!

Now, I suppose it's fair to question the idea of "function" when we're talking about dead wood pieces, as opposed to the living tree. Of course, the wood will not perform any nutrient export (any more than other types of aquatic wood does in any type of aquascape) or exchange salts, etc. The point here is that when we incorporate the wood into a brackish-water aquarium with a rich substrate (the other component of our brackish approach, which we'll delve into some other time), and some mangrove leaf litter, we're replicating the aesthetics and at least part of the function of the mangrove root habitat. In our opinion, it's a far more realistic and functional approach than the typical "rocks/white sand/seashell" approach than has been the typical "brackish" display tank for decades.

And, if you incorporate some live mangrove propagules and some adaptable aquatic plants (like our fave Cryptocoryne ciliata) into your display, you can have significant functionality (oxygen production/nutrient export from the plants), and the decomposing leaves and botnanicals can help foster, to some degree, a "food web" of microorganisms and macro fauna (snails, crabs, etc.) which can contribute to a more biologically-diverse closed ecosystem if managed properly.

This is sounding very much like our approach to blackwater/botanical-style aquariums, isn't it?


The idea of fostering a unique closed-system ecology and all of the challenges and benefits that can come with it is irresistible. And don't get me wrong- there will be challenges: We're talking about creating very rich, sediment-based substrates with a lot of leaf litter and some plants in a brackish water environment.

A lot of stuff going on here, right? On the surface, it seems like a recipe for trouble! I had many people telling me (without even trying this) over the years that it would be a total fail. They said "Too much bioload!" or "Your pH and alkalinity will be all over the place!" Or "Crash!" The reality is that, just like a blackwater, botanical-style system, it works really well if you use common sense husbandry techniques. Understanding bioload and utilizing the benefits of nutrient export via plant growth, denitrification, and water exchanges are the keys here. I've never had a crash doing this. I've never had a crash with a blackwater-botanical-style system, either, nor have most of you.

It's about how you manage the system. It's about common sense, husbandry, and observation. And taking some risks. And figuring some stuff out along the way as we get into it more. "Crowd- sourced" exploration of new aquarium approaches is very exciting, because we all learn together. Sure, some of the basic "proof-of-concept" has been done before, but putting it all together, playing with some of the nuances and subtleties, and applying finesse to it all- evolving the aquarium-that's still going to be an ongoing thing. Mimicking some natural processes from a complex habitat in the confines of an aquarium will be very challenging!

We have a lot more to discuss/debate/postulate/explore over the coming months with "Estuary", as more and more hobbyists are starting to play with this stuff and the botanical/brackish approach.

It's wide open for experiments, projects, discoveries, failures, and yeah- breakthroughs. We simply need to loose the chains of "how we've always done it" and  "that can't work because..." and move forward boldly and with an open mind, understanding that there will be challenges whenever we forge into previously uncharted territory. It's not "plug-and-play", or without any possibilities of failure. But the potential is amazing. Hope you come along for the ride.

It's super cool! 

Hope we've whetted your appetite and ignited your curiosity just a bit.

Exciting stuff. Different, yet familiar in many ways. Always challenging. Always enjoyable.

Something you might want to play with in your fish room when the first chill of autumn hits. 

Stay excited. Stay curious. Stay realistic. Stay engaged.

And Stay Wet.


Scott Fellman

Tannin Aquatics




June 25, 2017


Making the cut...

Like so many hobbyists, I enjoy virtually every aspect of aquarium-keeping. However, one of the parts of this game that always drives me a bit crazy is stocking! Now, it's not the aspect of, "I want more fishes than my tank can handle!" No, I'm pretty disciplined about that going in. With me, it's more of a question of, "Which of the 14 candidate fishes do I want to add to the tank?"

Is this a unique "Scott-Fellman-is-a-bit-wierd" problem, or do we all have this, to some extent? I suspect we all do...Okay, I HOPE we all do!

I mean, I generally know the types of fishes I want.

I am a huge fan of little characins, especially in my botanical-influenced "blackwater" aquariums. They are often found in these environments in nature. They're small fishes which aesthetically "fit" almost any-sized system and provide perfect "scale" for my aquascapes. I like them...no issues here. Where I run into difficulty is during that age-old debate: Let's say my tank can accommodate 50 characins of the size I am contemplating. Is it more interesting to have a dozen of four varieties, 16 or so of three varieties, or 10 of five varieties of characins? Or, do I just make it a "monospecific: tank and go for one large school of a single species?

Maybe it's not even characins. Maybe Rasbora! 

It's overthinking at its finest...and it's enough to make my head spin. It's the same with most varieties of fishes that we maintain in the hobby, isn't it? I know Mbuna people run into this stocking dilemma all the time- and the are people who maintain some of the largest aquariums in the freshwater hobby- they have a lot of real estate to work with! 

Traditionally, I've taken the "middle ground." I mean, this gives me a perfectly tolerable, yet still aesthetically-pleasing "ratio" of variety to aesthetic bliss. Depending on the size of your display, I've found over the years that having numerous varieties of fishes in a modest-sized (or even a large sized) tank is actually kind of...distracting! Seems like it's always nicer to have more specimens of less species. Sort of more like what you see in nature usually...

If we think about how fishes are distributed in nature, does it support this thinking? Well, not really..or sort of, depending upon how you look at it. In studies I've read about leaf litter systems in the Amazon region, a 200-square meter area was found to be home to about 20 different species of fishes! That's  surprising population density. Another researcher observed that Apistogramma are often found in nature at population densities of up to a thousand individuals in an area of less than 10 square meters!  That's a LOT of fish!

Now, in the case of the leaf litter studies, there is a reason for the species richness: Utilization of different parts of the litter bed by different species. In the Apistogramma study it was similar, in that the fiefs were distributed throughout a leaf litter bed of almost  a meter deep! Obviously, our aquarium are a lot smaller, and few of us could duplicate 3-foot deep leaf litter beds (nor would few of us want to..). And if you extrapolate down the size of the habitat to aquarium dimensions, you'd be working with a lot of species in a relatively small space i the "diversity" model, or a hell of a lot of Apistos in the "compact population" model! 

And then there are Lake Tanganyika shell dwelling cichlids...which live in huge aggregations in the shell beds...they sort of have their own model, right? I mean, they do really well when kept densely... So there are social as well as physiological factors at play here, huh?

There are numerous factors that contribute to population diversity and density of fishes in nature. In captivity...very few, right? I mean, it's our call, limited by available tank space, finances...and in some instances, our relative audacity! (don't underplay THAT!)

The reality for us is some sort of compromise. We need to juggle aesthetics, the ability of our aquarium to physically provide space for the given fish population, as well as the biological and mechanical filtration capabilities we can offer. Not to mention, the potential for aggression, predation, etc. is higher in such a densely-populated model!

So back to "square one", right?

Yeah, for me, it is. I'm about modest numbers of several small species...It's the fish geek in me who wants maximum "bang for the buck", as they say. I am okay walking that delicate dance between what I want and what I can provide..And doing it in a responsible, ethical manner. I fantasize about the 500-fish school of Tetras someday as the sole occupant of a larger tank- but the reality is the fish geek in me finds that a pretty tough pill to swallow!

Arrghhhh...More tanks. The solution is more tanks. That's it.

So I'm now narrowing down my final choices for one of my office tanks...seeing how many of which fish "makes the cut."

This is going to be interesting. And a bit agonizing...

Todays dissertation on density, diversity, and just me being a general pain in the ass.

Hope you have a great weekend.

Stay curious. Stay disciplined. Stay calculating...

And Stay Wet.


Scott Fellman

Tannin Aquatics

June 24, 2017

1 comment

The ephemeral nature of "stuff in the current..."

Not long ago, I was amusingly distracted watching my office aquarium, observing a little piece of leaf floating about in the current. I don't really know why, but it somehow made me ponder how different I have approached virtually everything in my botanical aquarium than I do in any other one I keep.

One of the things you get used to in a botanical-themed aquarium is, of course, decomposing leaves, softening botanicals, and the occasional strand of biofilm. And with these things, occasionally, a piece will break off and float around in the current...I remember in years past, in my reef tanks, or "clearwater" FW tanks, I'd be incredibly aggravated by little bits of "stuff" floating in the water column, and would pretty much drop whatever I was doing and reach for the net to remove the offensive material, whatever it was.

However, when I started playing with the blackwater, botanical-themed tanks, I realized that seeing the occasional bit of debris (typically leaves or "shells" of botanicals) didn't aggravate me in the least. In fact, I found that I kind of like it. I've watched enough of Ivan Mikolji's videos and seen enough of Mike Tuccinardi's pics of natural blackwater habitats to accept that the dynamic in nature is that, well- occasionally, there is "stuff" floating in the water.

And you just have to accept this in an aquarium that utilizes these natural materials.

Now, it doesn't mean that it's cool to have uneaten food, or huge pieces of leaves, dead fishes and such floating about in your tank. However, it does mean that little bits of stuff  sort of "goes with the territory" of what we do, and that this is nature. This is what happens in the wild, and there is no particular reason why it isn't acceptable to see it in our aquariums from time to time.

Again, it's one of those "mental; shifts" we have to make, understanding and appreciating the fact that the "aesthetic" of a blackwater/botanical aquarium is far different from the "nature aquarium" that has been presented to us in the aquatic press for so long. 

It's not an excuse for sloppy husbandry, or neglecting the removal of offensive materials. However, it IS a sort of acceptance of the fact that "stuff happens" in nature- and in aquariums- and that many of these things are simply not worth getting upset about. I mean, if you have an aquarium with brown water, and substrate dominated by decomposing leaves and softening botanicals, it shouldn't come as any surprise that an occasional piece might break off and float around before settling somewhere else in the aquarium. 

I find it strongly relaxing; oddly amusing, actually. Perhaps..maybe, these transient, ephemeral moments are the exact embodiment of the idea of "wabi-sabi" that Takashi Amano wrote about so often?

Just another nuance; another little transient thing- another mental shift we have to make when keeping one of these amazing aquariums.

Going with the flow...literally. Not stressing..just accepting. And appreciating.  Think about THAT the next time you see a little pice of leaf in the current...

Stay relaxed. Stay engaged. Stay appreciative. Stay obsessed..

And Stay Wet

Scott Fellman

Tannin Aquatics 

June 23, 2017


There is a season...

"To every thing there is a season, and a time to every purpose under the heaven."- Ecclesiastes

Okay, that's about as biblical a quote as you'll ever read from me. (I was thinking of it in the context of the 1960's folk song, however...). But it's perfectly appropriate for our little piece today, I think.

So I read that today,  there are apparently going to be 16 hours of daylight in North America.

Okay, cool.

Not really earth-shattering, as it's happened for eons this way. However, it got me thinking...Do we create true seasonal variations for our aquariums? I mean, changing up lighting duration, intensity, angles, colors, increasing/decreasing water levels or flow?

With all of the high tech LED lighting systems, electronically controlled pumps; even heaters- we can vary environmental conditions to mimic what occurs in our fishes' natural habitats during seasonal changes as never before. I think it would be very interesting to see what kinds of results we could get with our breeders if we went further into environmental manipulations than we have been able to before.

I mean, sure, hobbyists have been dropping or increasing temps for spawning fishes forever, and you'll see hobbyists play with light durations. However, these are typically only in the context of defined controlled breeding experiments. Why not simply research and match the seasonal changes in their habitat and vary them accordingly "just because", and see if you achieve different results?

We've examined the interesting igarape habitats of The Amazon, and how these seasonally-inundated forest floors ebb and flow with aquatic life during various seasons.

I think it would be pretty amazing to incorporate gradual seasonal changes in such a biotope aquarium, to slowly increase/decrease water levels, temperature, and lighting to mimic the rainy/dry seasonal cycles which affect this habitat. What secrets could be unlocked?

And what about annual killifishes? Would we get more predictable, achievable spawning results by mimicking the seasonal changes in a proper sequence? 

I don't know.

But it would be something cool to try. An interesting avenue to go down, right? Very simple thought for a Friday.

Consider it...

Scheme, plan, explore.

Stay excited. Stay Experimental. Stay creative.

And Stay Wet.


Scott Fellman

Tannin Aquatics 



June 22, 2017


Don't fear...Don't hate. Just grow.

I sometimes find that my blogs open up or expose an idea or issue that I hadn't really considered before. Other times, they reinvigorate older ideas I've held. Yesterday's piece on sumps in the freshwater aquarium (or general lack thereof, really) was one of those which reignited an ongoing "thesis" that I've had about the state of the freshwater hobby.

Okay, well, let's start it off by me pointing out that this is my opinion...based on personal observations and those of others I know. It's not the last word, or even the first word on the subject. You might find it a bit annoying. Perhaps even insulting a bit. Please don't take it that way. ("Good, Fellman, because who really gives a f---- what YOU think about it, anyways!")

In general, I think we're doing really well, and the "art and science" of maintaining all sorts of rare and unusual fishes, and breeding them, has never been better. The body of knowledge surrounding aquatic plants and their culture is growing rapidly. Aquascaping, although stuck (IMHO) in sort of an endless, "Groundhog Day" type of "loop" of derivations of one style, has progressed over the years (Well, if you can call 14,000 variations of the same idea "progression", of course- sorry snobby 'scape crowd...). Yet, for all of this advancement in the freshwater world, as a group, we seem a bit, well- stuck in our ways, or at least, reluctant to embrace different ways of approaching stuff.


It's not the first time I've seen this, nor the first time I've heard it discussed. While I often rail on my friends in the reef-keeping world for the laughable attitudes of "trend chasing" and hype that seem to be pervasive in that segment, there is one thing that's obvious in reef keeping that isn't in freshwater- an overall desire to embrace "new" without fear. As a reefer, you tend to want to try the latest and greatest stuff to get the edge that you perceive you need to keep your corals and fishes happy and healthy, and if new stuff drops in, you try it with little hesitation. Yes, that's an extreme, too...but it's progressive.

However, the freshwater hobby seems to be in a different sort of mode, if you examine it honestly. We are, in my opinion, willing to try new fishes, plants, inverts, etc. We're willing to look at some new techniques, if they seem to not deviate too far from what "everyone" says is okay. Yeah, it seems that for some reason, when it comes to some stuff, there is a complete lack of desire to deviate from established ways of doing things. It's like we compartmentalize it as "not for us" and that's that.

For example, going back to the sump thing...I can't even begin to tell you how many p.m.'s and emails I received from members of our community who expressed interest in the idea of using one, but were prefaced by stuff like "I had no idea this could be done" or "I always thought it was too complicated", or "It seemed to expensive or impractical.." and my favorite,  "I thought it wasn't for use in freshwater.." Stuff like that.

Where the hell is that coming from? 

I think it's an attitude. A sort of collective mind set. We seldom, if ever, hear it discussed. No authors seem to want to touch it. Okay, I will. There is no real "nice" way to present it. I have a theory, and you may not like it:

The FW world, although progressive in terms of animal and plant husbandry and propagation, is slow and reluctant to adapt to new technology or different approaches to things.  I mean, you are seeing adaptation of some reactors and controllers for "high tech" planted tanks, which is cool. You're seeing fertilization regimens embraced by a lot of these hobbyists. Cool. And you're finally seeing greater employment of advanced LED lighting systems. More (mass-market-available) foods that are comprised of organisms actually found in the natural environments of our fishes are coming into the freshwater market.

Why does it take so long? Why the stubbornness?

Don't agree?

It's glaringly obvious to "outsiders." (there should be no "outsiders", BTW- different topic for a different time!)

I get a lot of good-natured teasing from my fellow reefers that going to freshwater is like some groovy retro trip to the 1970's. Seriously. Look at the sump thing again. I mean, the sump idea has been around since the 1980's in reefkeeping, and some 30 years on, we see just a handful of them in freshwater, even though the benefits and potential breakthroughs that could be achieved by utilizing one are pretty obvious. Yet, we cling to our canisters and outside filters as if there is no better way to do stuff. We come up with a lot of excuses: "Well, most freshwater hobbyists have multiple aquariums..." or "Brine shrimp is more economical than the new preserved flies."  Okay, so a $300 canister system is cheaper than a $300 sump system? Not sure...I'm not attacking canister filters or frozen brine shrimp. Yes, they are great and they work well...but there are other ways to approach it. There can be some new stuff. We just seem so reluctant to give up the way we've always done things...the way everyone does it. The way "everyone" SAYS we should do it. "If it ain't broke, don't fix it..."

Don't like this? Don't believe me?

Look into Tannin's own history. When we first presented our approach to the blackwater/botanical-style system, the amount of pushback was significant. We were called "irresponsible" by many for proffering what they perceived as some reckless, casual foray into a "dangerous" and "unstable" world, with unproven ideas and methods. Stuff that few really played with. Or, some "old timers" told me "this is nothing new" (Which I agreed with), but told me it doesn't work without so much as steeping a catappa leaf. And the idea of seriously elevating blackwater aquariums floundered in obscurity or "novelty sideshow" status for years.

Yeah. Why?

Is it some desire to cling to the gentle ways of a bygone era, following the same well-worn path without some much as questioning why? 

Not sure. But it keeps coming up. I know I sound like a jerk for even discussing it like this, but it's my opinion, supported by numerous observations. Seems like it's almost a...fear. Or at least, a disdain. And I think it's really important that we just look at it and move forward.

Still with me? Good.

I know that many of you might not agree with me here. That's why I prefaced this piece with the disclaimer that it's my opinion.

And don't get me wrong. This rant is not targeted at everyone who keeps a freshwater tank. There is a lot of forward thinking in freshwater, but so much seems to get confined to a few categories, or held tightly in small circles. Not getting through the "noise" of the greater hobby narrative. I mean, look at shrimp fanciers, Rift Lake cichlid people, or Betta breeders. They're doing crazy shit. Why no generalized hobby progression or large-scale acceptance of some different approaches?  

Are we so compartmentalized/specilized/obsessed with our own specialties that we won't look outside the box? I have a hard time swallowing that. If for no other reason, I'd think manufacturers would want to integrate some new things into the mix. Pull over some of the sexy reef stuff and reconfigure/remarket to the freshwater world, who, once they overcome their initial reluctance to change will blow away anything that's previously been done with them in the reef category! Yes, it's great that we have more high-tech versions of the old stuff, but it sure is nice to apply totally new thinking "at scale" to our hobby, right? Besides, the FW world has a lot more buying power!

But it's not just about "stuff."

I think that some big-time freshwater hobby thought leaders need to do more to push progression which incorporates ideas from outside the boxes that we're comfortable in. I mean, look at the talent pool out there in the freshwater world! It's insane. We're breeding fishes that were once thought impossible to even keep alive! We're tissue-culturing and propagating rare plants that were once unobtainable  in the hobby, and shipping them around the world like they're Water Sprite. We have a collective patience that the reef keeping world seems to have only in tiny quantities at best. We can share that. The freshwater world has an amazingly talented group of lifetime, hardcore hobbyists who possess specialty knowledge and experience that is almost mind-boggling. 

Yet we seem close-minded in a lot of ways as a whole, IMHO.

Do we want to change this? I  know that I do.

So, how do we change this? (Assuming any of us want to..) 

We simply look outside of our boxes, peer over our fences, and think about how what's going on in other categories that can help us. You always see me talking about wanting to see more planted tank people get into botanical/blackwater systems because of their extensive knowledge of water chemistry, substrate management, and fertilization, for example. You hear me calling out my nay-saying reefer friends to try a blackwater or brackish tank and apply some of that "testosterone-fueled" thinking to freshwater. Because it works both ways.

We need to "cross-pollinate" a bit. We need to look at what aquarists are doing in other hobby "disciplines" and share and borrow and try out new ideas. And give them some of ours. Some won't work. Others will require lots of modification or adaptation. But the potential for breakthroughs is huge. Can't we all do this? I think so. Or is it just easier to reach for the outside power filter and call it a day?

I hope not.

I'd like to think that this 100+ year-old hobby simply needs a kick in the ass from time to time. We are like a bloated, arthritic giant that needs a wakeup call, a cup of coffee, and a hot shower. Once you wake up this amazing juggernaut and get it firing on all cylinders, the hobby as a whole will grow, with more kids getting into it, and more and more breakthroughs and progress than ever before. 

Again, many of you already get this. For those who don't agree, just contemplate before you trash me.

Don't hate on some new stuff from "the outside." We're all fish geeks, and we can learn from each other, utilize our experience, talent, equipment, techniques...Don't hate on change.

Time to wake up.

Rant over. Don't hate me. Think about it. Dismiss fear. Accept this easy challenge. Blow up the hobby even more. Achieve more great things. Grow.


Stay driven. Stay thoughtful. Stay innovative. Stay motivated.

And Stay Wet.


Scott Fellman

Tannin Aquatics 


June 21, 2017


Back to the sump...

I am a big believer in sumps.

Yes sumps.

I know, you have visions of an absurdly-complicated reef system, with every possible gadget attached to the tank, costing thousands of dollars/euro/pounds, etc., while yielding only marginal performance benefits over more "conventional" freshwater filtration systems, right? Well, first off, don't think of a sump as a "filter" in the conventional sense. Think of it as a sort of "water management system" for your display. To call it a "filter" is way too simplistic, IMHO. And it doesn't need to be a byzantine maze of complexity, either.

Although it can accomplish a lot of complex tasks, a sump need NOT be complex. In our context, a sump could be defined as virtually any type of container used beneath or behind an aquarium. It holds water and provides a location to place various pieces of equipment that our systems need (Yeah, even a setup consisting of a simple spare 10-gallon aquarium set up below your 50 gallon display tank to receive and process water is a "sump" by this definition).

Now, coming from a reef aquarium background, where sumps are simply the way 99% of reef systems are set up, this probably doesn't surprise you that I like them. The need to accommodate ancillary support gear like protein skimmers, reactors, etc. is just one reason why sumps have evolved into the "nexus" of most reef aquarium systems.

Yet, the more I play with exotic ideas in my freshwater and brackish water systems, the more I'm realizing the value of the sump, and how they can benefit freshwater hobbyists as well. I'm always surprised to see high-end setups with canister filters and reactors and such instead of sumps. Seems sort of..well, "clunky" to me. We see them in some Discus tanks, African Cichlid systems, and occasionally a planted tank, yet they are the exception, rather than the rule. I'd love to see their use more widespread in the general freshwater world. Now, I realize that the breeder who keeps a hundred 5 and 10 US-gallon aquariums is unlikely to want set up a sump for each one, and the idea of a central filtration system (wether incorporating a sump or some other system) is fraught with potential issues, such as transmission of disease, etc.

However, I think sumps would be a good idea for most freshwater display aquariums. I think that even modest-sized aquariums (like 40 US gallons and up) could benefit from sumps. Now, yes, there is the issue of expense and additional design considerations...You're essentially adding another little aquarium. And of course, you need to have an overflow weir, which means a "reef ready" tank (unless you want to do some retrofitting and install an overflow). And a reliable submerged or external return pump, sized properly for the system.  Yeah, a bit more work, perhaps, than simply hooking up the old Eheim... 

Then again- dealing with glassware sort of sucks, IMHO!

For advanced concept or speciality display tanks (like our blackwater and brackish-water systems), sumps offer extraordinary flexibility and advantages over more traditional systems, like canister filters, sponges, and outside filters. I mean, the aesthetics alone are reason to consider such an arrangement...no hardware visible in the aquarium is always a plus in my book. A sump allows you to place the heater, reactors, or other tech equipment conveniently out of view, yet easily accessible for access and maintenance.

That's all well and good from an aesthetic standpoint, but what other reasons would there be to use a sump in one of our systems? What are some tangible benefits? Well, to start with, I like them because they add water volume to your overall system, A typical sump (in the reef aquarium world) is anywhere from 20% to 50% or more of the volume of the display itself. And of course, this adds volume to your overall system; volume means additional stability and biological capacity for your display. And a built-in "hedge" for evaporation. Sumps also facilitate Increased oxygenation. As water drains into the sump, air mixes with it, allowing for beneficial gas exchange, releasing CO2 and adding fresh O2.

(My friend Marc Levanson builds awesome custom sumps and has a great website filled with info on them..check it out)

Sumps allow you the flexibility to utilize different types of (filter) media, like botanicals/and leaves in our case, than for whatever reason, you might not want in the display tank.

Leaves, in particular, with their associated decomposition, biofilms, and aesthetic considerations may be something that you simply don't want in your aquarium...but you might like the affect they have on the aquarium, in terms of environmental stability, cultivation of biological filtration, supplemental food sources, etc. Or maybe you want to play with live plants and not have botanicals "in situ"- or perhaps you want a "clinical" bare bottom Discus or other "concept" tank, but appreciate the "support" a sump could provide.

(I mean, you CAN really go crazy with all sorts of media in a sump if you WANT to..)

And of course, with a sump, you can build in sections for the cultivation of these food animals (like Daphnia or worms, etc.), creating, in effect a refugium of sorts to grow them free of predators (your fishes), feeding off of excess food and processing nutrients, with the occasional specimen getting pulled into the main display to provide the odd "treat" for your fishes. 

You could even light a section of the sump (on a "reverse" schedule of the display) with an inexpensive LED light to cultivate fast-growing floating or rooted bunch plants (like Water Sprite, Rotala, Hornwort, etc.) to assist with nutrient export via harvesting them. Oh, and a great "hack" for those who love nice aquatic plants but also happen to keep disruptive fishes i the display (like digging cichlids, vegetarian fishes, etc.).

These are just some of the most prominent and beneficial reasons for considering a sump for your next display aquarium. Sure, you could adapt a canister to perform some of the functions (like holding "media"), or use a hang-on power filter as a sort of "moss reactor" or what not, but the concept of a sump, with it's spacious capacity and inherit flexibility gives you options and ease of operation that these "band aids" simply can't match. The additional expense and planning that might be required when incorporating a sump into your next freshwater display will, in my opinion, easily be compensated for by the operational effectiveness and efficiencies you'll realize. Even the "all-in-one" aquariums, which are becoming more and more prevalent in the freshwater world, offer the benefits of a sump (multiple chambers, extra water capacity, etc.).

All-in-all, sumps are a great way to give your system the "edge" it might need for long-term success and "mission flexibility" as your needs evolve or change. Are they perfect for everyone? Absolutely not, as we discussed at the beginning of this piece. However, for many of us, they could open up exciting new possibilities for adventurous hobbyists with ambitious ideas...and that's kind of what we're all about, right?

Stay open-minded. Stay creative. Stay innovative. Stay bold.

And Stay Wet.


Scott Fellman

Tannin Aquatics


June 20, 2017


The Fish Room- A place of wonder...a place of magic.

A few years back, I was fortunate enough to have a fish geek experience that really made me sit back and think about this crazy hobby of ours in a whole new light. I attended a meeting of a local club in Duluth, MN (Yeah, in February! It was a bit colder than L.A. in February...LOL) to give a talk, and got to stay at the home of a dedicated hobbyist- My friend and prototypical all-around fish geek Matthew Pederson (of Amazonas and Coral Magazines...his blogs and articles are awesome BTW)- and his very serious fish room!  I swear I spent as much time down there as I did with him. It was the first time in a lot of years that I was exposed for more than a few hours to a dedicated home fish room. I even got to scrape algae for him; epic! Felt great. The memories of that brief weekend hanging out in a serious fish room really got my wheels spinning. Something in my "programming"- in our collective "programming"- makes it feel "aspirational." Oh, what was that I wrote, a "fish room?" You got it. A room filled with dozens of aquariums of varying sizes (freshwater and saltwater!), dedicated to the study, care, breeding- and sheer joy of fish keeping.

Now, a fish room is not at all an alien concept to many of us, although we don't hear about 'em as much as we did in the past. And some of us have never had a fish "ROOM", per se- just a lot of tanks scattered around various locations throughout our residence! However, the idea of a dedicated fish room, with all of its exciting little nooks and crannies and potential- is the stuff of dreams for many of us, right?

Fish rooms used to be a lot more common in the hobby. Serious hobbyists thought nothing of filling their basements, garages, and extra bedrooms with lots and lots of aquariums. It seems that in the last few years, the fish room has gone the way of the CD- a once pervasive product that seemed to just sort of fade away. Unlike the CD, technology did not force the idea of a fishroom into retirement. Rather, technology has benefitted the hobby immensely, making it easier than ever before for a hobbyist to create his or her own little nerve center to practice the state of the art in aquarium keeping with several aquariums.

Yet, for some reason, the multiple aquarium fish room was starting to become a thing of the past. Maybe it was economics; time, or the demands of other areas of life that made the commitment to a room full of aquariums seem impractical. For a long time in recent decades, dedicated fish rooms were just the domain of the hardest of hardcore fish geeks...However, with all of the new focus on conservation and fish breeding, it seems like a resurgence is in the works on a large scale!

And for the first time, marine fish breeding is starting to move beyond just Clownfish, and it seems like we’re starting to see some serious breeders move to trying to reproduce all sorts of fishes. And even when not breeding fishes, dedicated marine hobbyists are devoting entire rooms to their obsession, and are pushing the state of the art forward every day. An interesting overall hobby change.

And of course, crazy freshwater fish breeders are popping up everywhere- and along with them, multiple tank fish rooms! Check with any club's Breeder's Award Program if you don't think that's something that's happening all the time!

And, yeah, some of us took it to far and opened up an entire warehouse full of fish stuff... All part of that weird thing of just being a round a ton of fish tanks most of my life. I think that, on some level, all of those of us in the business- whether we care to admit it or not, sort of use the "business" as a cover to play with fish tanks full-time! 

For the hardcore hobbyist, it's no different. The challenge is to fit it into our lifestyle. Sure, given factors like economic uncertainty, time pressures, and other commitments, today’s home hobbyist is more pressed than ever to find time for his or her hobby, even for one aquarium, let alone a dozen or more. Yet, there is something about this hobby that makes it so hard to stop at just one aquarium, isn’t it? And we keep going...

What we only half-jokingly refer to as “Multiple Tank Syndrome”- the "addiction" to the hobby that gives us the urge to set up more aquariums-is alive, well, and very real! We have so many ideas, and a desire to try them all...and it seems the only way to do it is to set up more and more aquariums..!

Some people collect souvenir shot glasses, coins, or cats. 

We collect aquariums. And fish. And plants. And all of the "junk" that goes with 'em.


It seems that with every dedicated hobbyist, there is the desire to expand or horizons, to try new things, learn about one more fish, plant, coral, ecological niche, etc. And that requires "just one more" aquarium... or perhaps a few more! It requires the need to expand, explore, and experiment.

To this I say- Go for it! Don’t fight the urge to get that next aquarium. Not only are you giving yourself something that you will enjoy immensely, you might just be able to try something altogether new, break new ground, or better yet-inspire others to persue their aquatic dreams. Maybe you don’t have the space or finances for a true "fish room", but satiating your desire with another aquarium somewhere in the house is a good start!

As a child growing up in a fish-geek household, seeing my dad’s many tanks virtually cemented my destiny that someday I’d be deeply involved in the aquarium field. I always had more than one bowl, plastic container, or aquarium in my bedroom...and all over the house, eventually.

I was inspired, man! Couldn't fight it off...Who knows what kid might be inspired to entire the science field as a result of a visit to your fish room? Or just your fish tank? Or tanks? I mean, virtually every household has more than one car, so why not more than one aquarium? It's a good thing...Well, at the very least, it’s good for the aquarium industry! (Sorry, couldn't resist that one...LOL)

l’ll say it again: "Fish room." A place of magic. A place of wonder. A place of awe. A laboratory. A retreat. A launch pad for dreams. I dedicate this post to all of you out there who practice the art of aquarium keeping each and every day, regardless of if you have one fish bowl or 200 tanks in your basement. You are the very essence of the hobby- the living, breathing soul of our passion. I say it again: If the muse strikes, don’t fight it. Why stop at one?

Who has a "fish room" going? Who's contemplating setting up one? Or at least, who admits to having "Multiple Tank Syndrome?"

My advice to you if you?

Set up another aquarium! 

Oh, and I know this website where you can get really cool botanicals if you're feeling the urge to try blackwater... (heh, heh, heh...)

Until next time,

Stay Wet


Scott Fellman

Tannin Aquatics

June 19, 2017


If things were perfect...

If things were perfect...

Your LFS would be open 24/7/365!

Plants would never have snails, Hydra, and other pests.

Die, scum! You've been banned.

My plumbing connections would never leak; in fact, never even "sweat!"

Pods would sink to the bottomon the first try.

The expression “Limited Edition” would be banned from the coral industry.

Activated carbon wouldn’t need rinsing before use!

Acrylic would never scratch!

All Knifefish would max out at 4". (Can you imagine a "DWARF BLACK GHOST KINFEFISH!")

Flexible tubing would be easier to straighten out!

Discus wouldn’t be so darned fussy.

All salt mixes would mix up instantly to 1.025. Or 1.003!

Hatchetfishes would be incapable of jumping!

I wouldn’t keep gluing my fingers together when I play with coral frags!

“Wireless” pumps would actually have NO WIRES!

Shipping services would never mess up a delivery.

Aquatic putty would actually stick to stuff.

Frozen foods wouldn’t get freezer burn.

"Silent" overflow weirs would be completely silent.

Aquarium heaters would never fail.

A "reef safe" marine angelfish would be 100% "reef safe."

Live Black Worms would need no rinsing or refrigeration!

LED controllers would make it impossible to set your color to “Windex Blue.” (sorry reef world)

“Tank Of The Month” contests would be banned forever.

Driftwood would need no rinsing or soaking before use…ever.

Wild Apistos would eat frozen foods right out of the bag.

All coral vendors would use the same color settings and standards for their photography.

Pipefish would be super easy to keep and breed, and eat flake food!

"Eats TetraMin right from your fingers! Drops babies every 2 weeks....!"

I’d have an endless supply of complimentary Turkish towels! (800 thread count or better, of course)

Some Tetra would come in a deep, metallic purple color!

Frag saw blades would never get dull.

You'd never have to clean algae from glassware in your planted tank!

Fish would swim INTO the net on the first try, and be totally calm...

Those are like my first couple of dozen or so…let’s hear yours…

Stay hopeful. Stay relaxed. Stay calm. Stay creative.

And of course, if things were perfect...everyone would...

Stay Wet.

Scott Fellman
Tannin Aquatics

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