Do you like murky waters? Do you want your fish to swim through a cloud of dead plant matter that represents fetid swamps and decaying life?

Bleh, doesn’t sound very appealing does it? Well, we shouldn’t be too quick to judge. You know what they say: beauty is in the eye of the beholder.

It’s easy to go with a conventional aquascape. Sparkling clear waters and beautiful tropical fish have universal appeal. Every once in a while, though, you come across an oddball aquarium that has its own unique allure. Such is the case with blackwater aquariums. These aquariums replicate the stagnant waters in ponds, creeks, and swamps that get very little fresh water. The result is something like this:

Tea-Colored Waters of a Blackwater Aquarium

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Wait a second. If these are supposed to be blackwater aquariums, then why are they brown?

Yeah, I was wondering the same thing. I’m not sure who named these things — probably somebody who’s color blind.

Anyways, that tea color comes from the dead plant matter in the aquarium. Whenever a plant sits in water for a while, it gradually releases tannin. Normally the tannin gets washed away by the flow of water, but when the water just sits there it gradually collects over time. Fun fact! Leather workers use tanning to tan animal hides, which is where the phrase “tanning” comes from. You probably thought that tanning involved putting the leather out under the sun didn’t you? It’s OK — I used to think the same thing too.

The reason why you never see tea-colored aquariums is because aquascapers go through painstaking efforts to make sure the water doesn’t have any impurities. They boil driftwood to get rid of any tannin and they also run water pumps to keep the water clean. These blackwater aquariums embrace natural chaos by treating the tannin like a main feature.

Blackwater tanks probably aren’t for everybody. I suspect that when a lot of people see a blackwater aquarium their first reaction would be, “Is it supposed to look like that?”

Autumn Shades of a Blackwater Aquarium

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Well, the answer would be, “Yes,” of course. But don’t think that you have to conform to the expectations of others. If blackwater aquariums tickle your fancy, then go for it!

Sources of Tannin

The trick to making a blackwater aquarium lies entirely in the plant matter. Aquascapers incorporate dead leaves, rich soil, and fallen branches into aquariums in order to provide a rich source of tannin. You also have to cut out the carbon filter in your water pump. Having all of that tannin is pointless if your pump is constantly getting rid of it.

Blackwater aquariums may not be as popular as conventional aquariums, but they really can add a lot to a room’s atmosphere. The amber waters are in very soft, warm tones that can add autumn colors to a living space. One of these aquascapes would fit in beautifully with a room that has a lot of wood surfaces. Businesses that highlight lots of orange and browns in their logos and custom uniforms might also want to consider an office blackwater aquarium.

Blackwater Aquarium

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If you do decide to make a blackwater aquarium, then there are two major things that you really have to watch out for. First of all, blackwater aquariums have a unique impact on the water quality. The tannin makes the water softer than normal and it also increases the acidity. You will need to take extra care to make sure that the water is within the healthy range.

Fishy Romance

The other interesting quirk of blackwater aquariums is that it’s incredibly romantic — for fish, I mean. When humans think of romance, we imagine the top of the Eiffel Tower, a candlelit dinner, or a long walk on the beach during sunset. Fish like to imagine the murky depths of a blackwater aquarium. Bow-chick-wow-wow!

That’s right — your pH levels won’t be the only thing getting down and dirty in your blackwater aquarium. You can expect to hear the pitter-patter (or splishy-splash) of newborn fish.

So, is a blackwater aquarium right for you? Maybe so. Don’t let the dark waters scare you off. Once you get past the initial surprise, it’s easy to see why some aquascapers adore these unique aquariums. They’re actually kind of beautiful in their own special way — reminiscent of the colors during a sunset, don’t you think?