Breaking down the stuff that breaks down in our tanks...

A lot of hobbyists ask me about maintenance of blackwater/botanical-style aquariums...We are at a phase in the BWBS "evolution" that is creating some real "technique"- and that's pretty exciting!

Siphoning detritus is a sort of "thing" that we are asked about near constantly. Now, the idea of "detritus" or "stuff" takes on different meanings in our botanical-style aquariums...Our "aquarium definition of "detritus" is typically agreed to be dead particulate matter, including fecal material, dead organisms, mucous, etc. And bacteria and other microorganisms will colonize this stuff and decompose/remineralize it, essentially "competing" the cycle.

In the reef aquarium world, where I have operated for decades, you'll see a lot of hobbyists freak out about "detritus" and such accumulating in the aquarium, and they blame filter socks and media for all sorts of problems in their aquariums. I understand this concern for water quality, but I think it sort of places emphasis on the wrong part of the equation; that is, what exactly is accumulating, and why? Uneaten food? Bad! Need to be more careful here. Fish waste? Unavoidable to some extent (unless you lower population density/food inputs).

You get the idea...

I think it's all relative, though. 

In a botanical-style blackwater aquarium, we tend to see a fair amount of fine "bits and pieces" of decomposing leaves and botanicals accumulate in our mechanical filter media. Funny thing to me is that this stuff, although somewhat unsightly if allowed to accumulate in the aquarium, seldom is seen doing such. And, it's just sort of "there", if you know what I mean. And, other than potentially being visually distracting, this material is not really detrimental- I mean, you want it in your system (at least in its "original" form).  It's what imparts the tannins, humic substances, and other desirable compounds into our water.

And is it really that "unsightly?"

I'm not completely convinced that it is. The look of the broken-down botanical material isn't beloved by everyone, but it IS a natural thing, right?

Well,  If it's uneaten food, on the other hand, you need to figure out a more accurate feeding approach. "Detritus" in general, in my opinion, gets a kind of a bad rap, as the bulk of it is really broken down already by the time it accumulates. Sure, in systems with large, predatory cichlids and messy eaters, you're likely to see a lot more than you would in a lightly-stocked tank with say, Endler's Livebearers, small Rasbora, or Gouramis, but most of us really overfeed THAT much?

I don't think so.

Of course, if you see uneaten food and such accumulating in your tank, it looks crappy. However, do you have phosphate or nitrate issues as a result of accumulating organics from this stuff, or is some of it- enough of it- being utilized by bacteria and other "unseen residents" of your tank that it's not really a "problem" from an environmental standpoint?

Regular water exchanges are a great way to keep this balance, as you've no doubt have had beaten into your head since your aquarium-keeping "infancy." And sure, you need to test your water to get a "snapshot" of what's happening in your tank.

The basics.

So...we're back to the beginning, yet again.

Is "detritus"- menace or benefit? Or perhaps, something in between? Like biofilms, fungal growth, aufwuchs, and decomposition- is it something that is inevitable, natural- perhaps even beneficial in our aquariums? Or, is it something that we should learn to embrace and appreciate? All part of a natural process and yes- aesthetic- that we have to understand to appreciate?

My personal thoughts? Keep it clean, but don't get overly concerned about the material breaking down in your tank. Take it out...leave it's your call.

Embrace the natural process which occur in your system. 

Simple thought for today.

Stay curious. Stay bold. Stay excited. Stay methodical.

And Stay Wet.


Scott Fellman

Tannin Aquatics 


Scott Fellman
Scott Fellman


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