Looking for information on blackwater biotopes

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I'm thinking of setting up my 600g with a blackwater biotope next and was wondering if anyone has experience or links to some informative articles.
Blackwater aquatic environments have low PH, low GH, low light, high tannin content and few plants.
 
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I don't have any info other than referring to aquarists which I'm sure you already checked. They are always my go to place for new pond concepts. They seem to have done everything possible in the aquatic realm and always lots of data and detail.

I did run a pond for a few years that was high tannin, low O2, low light, no plants but it wasn't intentional.;)
 
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Yes, I've read lots of questions and guesses, but not much for a clear direction.
I'm interested on how a blackwater environment handles C, N and P and how the fish you see for sale behave in a proper environment.
I'm looking for lighting information as well.
I've come across this article for a start. Haven't read it all yet.
https://www.witpress.com/Secure/elibrary/papers/WS13/WS13002FU1.pdf

I've also come across this site for supplies:
https://tanninaquatics.com/

.
 

Meyer Jordan

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Interesting.I never knew that there were aquarists that were into duplicating Amazonia conditions, but not really surprise either.
I am sending you via email three (3) research documents that I found relating to this subject. They may or may not provide you with any useful data. I didn't take the time to read them
 

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I love your new experiments @MitchM . Please post pictures and update us if you decide to do it!
 
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Thanks cas, I will do.
I'm pretty intrigued so far at the absence of plants in a blackwater biotope.
I came across a few videos of the Rio Negro in Brazil and it sure doesn't look like any aquariums I've seen before, yet it's the natural habitat of many tropical fish we see for sale.

 
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So far, I'm not really liking what I'm seeing as far as what constitutes a blackwater biotope aquarium on various websites.
There seems to be a focus on appearance rather than function.
All I'm seeing so far are new setups that use only sand, leaves and driftwood. I'm not seeing any long term setups.
The problem with a sand only substrate in a closed system is that it will lead to an excess buildup of organic material that will turn anoxic and release H2S over time, which will harm the aquarium inhabitants.

I'm leaning towards a more organic based substrate (topsoil) where microbes will break down organic waste into more fish friendly elements. This is of course a compromise because an aquarium is a closed system.
In the natural blackwater river basins, water flow is lateral, which is where a constant supply of new water will flow down along the substrate layer and out to an ocean.
That takes me out of a typical biotope classification.
 

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In the natural blackwater river basins, water flow is lateral, which is where a constant supply of new water will flow down along the substrate layer and out to an ocean.
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And it would seem that this is where your set-up problem lies.,for it is this lateral water flow that contributes to and creates the 'blackwater' environment in the first place.
 
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That's the case with any stream ecosystem, with blackwater there are very few plants to help with nutrient export.
 
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So far, I'm not really liking what I'm seeing as far as what constitutes a blackwater biotope aquarium on various websites.
There seems to be a focus on appearance rather than function.
All I'm seeing so far are new setups that use only sand, leaves and driftwood. I'm not seeing any long term setups.
The problem with a sand only substrate in a closed system is that it will lead to an excess buildup of organic material that will turn anoxic and release H2S over time, which will harm the aquarium inhabitants.

I'm leaning towards a more organic based substrate (topsoil) where microbes will break down organic waste into more fish friendly elements. This is of course a compromise because an aquarium is a closed system.
In the natural blackwater river basins, water flow is lateral, which is where a constant supply of new water will flow down along the substrate layer and out to an ocean.
That takes me out of a typical biotope classification.
I think if you use a thing layer of sand, and have fish/snails that turn-over the sand, you don't need to worry too much about H2S. Another option is to regularly "overturn" the sand with a gravel vacuum.
 
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I think if you use a thing layer of sand, and have fish/snails that turn-over the sand, you don't need to worry too much about H2S. Another option is to regularly "overturn" the sand with a gravel vacuum.
My main two interests are substrates and water quality.
I think that if I can adequately control those two things, everything else will have the best opportunity for a healthy life. I would prefer to let as many natural forces do the work as possible, within the limitations of an aquarium.
The Amazon river basin is a pretty interesting ecosystem from what I have read so far. Everything from obtaining minerals annually from the dried areas of the African lake Chad to an almost sterile water PH of 3.5.
Vacuuming the substrate kind of goes against my nature.;)
I'm getting the setup ready now, so I'll be starting a separate thread.
 

Meyer Jordan

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That's the case with any stream ecosystem, with blackwater there are very few plants to help with nutrient export.
Yes, but the differences between a typical forest and a rain forest are many.

As little as 2% of sunlight ever hits the rain forest floor. The average temperature is 27C and because of the high annual rainfall humidity is high. The temperature, lack of sunlight and humidity all contribute to rapid organic decay and the rainfall quickly leaches the released nutrients. The heavy annual rainfall also imparts a fairly swift current to these blackwater environments quickly flushing any leached nutrients farther downstream leaving the blackwater nutrient poor.
In the video that you posted several things are noticeable: a substantial layer of organic matter in various stages of decomposition, a lack of green periphyton (which translates into low Oxygen levels), and a fairly high TSS.
Blackwater streams are also very acidic, low or entirely lacking in KH and GH and have a very low level of conductivity.

I found this definition to be quite useful-
"Black-water rivers. The water in these is brown and rich in humus. Its
transparency is only about 1-5 m, although there are no significant amounts of
suspended inorganic particles. The brown water is always very acid (ph
3.7-4.7) and poor in inorganic ions. The humic substances--either dissolved
or colloidal--are linked with a special soil type, a tropical lowland podsol.
which is a bleached white sand covered by the Caatinga forest of the Upper
Rio Negro." River Ecology, B.F. Whitton

Truly recreating and sustaining all of these required conditions in an aquarium environment would seem to be quite a daunting challenge.
 
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