The River Tank provides a cross-section view of a "river". The water circulates through the tank, flowing into and out of several pools of different water levels. Fish delight in swimming against the current streaming out of each pool. Using short bursts of speed and making a slight splashing commotion, the fish propel themselves up to the next level. As the water falls, the turbulence forces air into the water and eventually the tiny trapped bubbles slowly rise back to the surface creating an ebullient effect. The sight and sound of the rippling water and the activity of the fish creates an ever present state of motion that is fascinating to watch.

The Tank

This River Tank was created using a River Tank Ecosystem kit. Originally, the River Tank was sold by FinnStrong Inc., the kit is currently marketed by Perfecto Manufacturing. They now offer a "New River Tank" kit that has a more natural design. Unfortunately, Perfecto only sells to retail pet stores. The kits can also be purchased from biological supply companies - or

The kit consists of plastic inserts that are installed inside a glass tank using silicone sealant. The inserts divide the tank into separate pools and also provide hollow spaces under the water and ledges above that can be filled with gravel to support land plants. The upper pool is 12 inches deep, the middle pool is 10 inches deep, and the lower pool is 7 inches deep. The tank is 55 gallons (48"x21"x12"), but is filled with only approximately 20 gallons of water.

To circulate the water, a Rio Aqua Pump 1400 is submerged in the lower pool where the nozzle of the pump fits into the wall of the filter chamber. The filter chamber is designed to fit the extra large Whisper Bio Bags. There is a spill-over channel starting at the top of the filter chamber that carries the water from the filter chamber back to the upper pool. A submerged Tronic 100 watt heater located in the upper pool keeps the water at a constant 74 temperature.

I obtained my tank second-hand. The tank had been used for some time and needed to be cleaned. I removed the inserts from the glass walls using a razor blade and then thoroughly cleaned them and the glass. The plastic inserts had a mottled blue-grey color originally which I thought made the tank look very gloomy. Although I knew it would take some effort, I decided to cover each insert to improve the look. I bought clear aquarium safe silicone at the hardware store (GE 100% Silicone Rubber Sealant Window & Door) spread it over each piece and then sprinkled small-grain horticultural sand on until each piece was entirely covered. The result was a plastic insert that looked like rock! It really made a great improvement on the appearance.

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Top Pool of the River Tank Middle Pool of the River Tank Middle Pool and Channel Channel Lower Pool of the River Tank Side View of the River Tank Top Pool Top and Middle Pools Middle Pool Lower Pool Submerged Pump in Lower Pool Water Flowing Out of Top Pool Lower Pool Showing Pump

5 Second Videos (Click on play button to start)

Side view of the river tank running.
A danio jumping to the upper pool.

Land Plants

The land plants in the River Tank are ordinary houseplants purchased at a local garden store. I selected small plants in 2" plastic pots. I hadn't researched plants that prefer a well watered environment, but all the plants I chose are doing well. I took the plants from their containers, removed all the dirt, and planted the bare roots into the gravel. The plants are growing hydroponically, taking in nutrients from the water seeping through the gravel. The plants growing on the ledges are watered daily by hand because I prefer not to have a glass cover on the tank (which would increase humidity). The plants are thriving under the fluorescent lighting from the two 40 watt strip lights above. One of the polka dot plants actually bloomed purple flowers, something I had never seen before on these houseplants.

Some land plants in the River Tank:

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Plants at the top pool Plants above the channel Plants above the lower pool Channel Plants Closeup of plants Lower pool plants Polkadot plants Aluminum plant

Aquatic Plants

The aquatic plants that are in the River Tank are those that don't require as much light. The strip lights are well above the surface of the water, therefore some of the plants requiring stronger lighting just didn't do as well (like Cabomba).

Some aquatic plants in the River Tank:

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Aquatic Plants in the River Tank Aquatic Plants in the River Tank Rotala Indica Cryptocoryne Hornwort Hygrophila Polysperma


There is a diverse fish community in the River Tank consisting of:

The sleeker danios move effortlessly from pool to pool. The stronger/bigger danios stake out territories in the upper and middle pool, while the rest have to make do with the lower pool. The adventurous danios are entertaining to watch. They are always out in the open chasing each other around and around.

The stocky corydoras are surprisingly strong enough to fight the current to make the jumps, the two albino cory cats remain exclusively in the upper pool.

The gold barbs are usually venturing upstream, trying to find each other.

I have found that the loaches love the strong currents, they have the best body form for traversing up and down the river. They seem to have curious personalities to boot. They have cute eyes and whiskers and seem to be very aware of people. They like to remain mostly hidden behind pieces of wood but stick their heads out to see what is going on. I had to install a plastic grate where the water flows into the top pool beacause they were constantly trying to keep moving upstream. I found a few swimming in the channel where the water flows from the filter chamber and in the fliter chamber itself! So far it has contained them but they might figure something out.

The neon tetras are much more active in the river tank than the regular tank they were in previously. In the morning I find them all together, either in the lower pool or the upper pool, so they are able to get through the currents. They are adults and are fairly big, smaller neons would have more trouble I would think.

In the past when I had three Paleatus corys in the tank, I observed them spawning and laying eggs on the glass in the lower pool. I've never seen that happen in any of my other tanks, I think the moving water and naturalistic setting inspires them.

I had tiger barbs in the tank before as well, but because of their deep bodied design they couldn't get to the second pool as they matured.

It seems that the activity picks up at night after they are fed and when the lights go off. I can hear the fish jumping to the higher pools. Most of the fish besides the danios are more nocturnal types, however, they are still somewhat active during the day.

Danios, having a streamlined form and hyper nature, are the most active in the community, flittering from pool to pool.

I feed my fish an assortment of food: frozen bloodworms,sinking wafers for catfish, shrimp pellets, flake food, spirulina flakes, mini floating fish pellets, floating food sticks, and algae wafers. The gold barbs, and danios, and neons all have bright, vibrant colors due to their constant activity and varied diet.

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Albino Cory Chasing Barbs Cherry Barb Clown Loach Communtiy Fish Zipper Loach Orange Barb Two Loaches Loach and Barb Gold Barb Two Corys Small Fish


The maintenance of the River Tank takes a minimal amount of time. I try to perform a partial water change every week or so, changing approximately 4-5 gallons. I add approximately 1-2 gallons of water a week to replace that lost from evaporation. An algae-pad scrubber is used to clean the front of the glass. The Bio Bag filter, changed every month with extra charcoal and ammonia chips added, keeps the water crystal clear.


Interesting links I have found: