Biotope One A Study of Flora and Fauna 
By Edward Johnson
I was looking for an inexpensive way to keep larger fish for breeding and for grow out tanks for the fry. The fish room was downstairs in the unfinished basement and getting a 200 gallon glass or even acrylic tank down there was impossible.
One afternoon a friend called me and asked me for some advice and a hand. With Sawzall in tow I went not sure of what to expect. When I arrived I saw a few stacks of IBC totes in the backyard. Immediately I knew this would work for my fish room needs.
I had to cut the top down to get it through the hall and down the stairs but it worked out well. The shallow top part was great for raising livebearers and other similarly breeding fish. The much larger lower was perfect for the larger egg laying cichlids to use for breeding. It also was a great grow out tank for fry for various fish.
I cut the metal cage in the middle of a row in order to use a cedar frame on top and bottom to add to the aesthetics of the setups. Carefully measuring the frame I made sure the metal parts would be in the center of the frame on the top. Using a pencil I marked where each tube would rest and drilled it out to a uniform depth so any weight would rest evenly throughout the upper frame even though it wasn’t apparently an issue anyway. A few screws through the frame into the tubes and I could move the entire IBC tote as a unit by myself.
To save space I put the cut off upper part upside down onto the lower part and offset it partially. These shorter containers I bred xiphophorous predominantly, mostly the wild types. They are large enough for most smaller fish to breed in and can be used to grow out smaller fish. The lower parts of the totes I housed the bigger cichlids that needed the room and dedicated space to avoid aggression. The larger totes were also good to grow those fry out in.
One tote I used for hydroponics. The lower housed tilapia and crayfish. Up top the substrate was hydroton clay balls and housed a bell siphon. A pump in the lower slowly pumped up water to the upper level. Once a certain level up top was reached the bell siphon drained it all back into the lower. A bell siphon is the same principal a toilet works with.
The upper hydroponic area had earthworms in it that ate detritus that accumulated from the water below. The hydroton held lots of nitrifying bacteria and acted as a wet dry filter for the tilapia below. The draining water swept away to the tilapia and crayfish a treat of earthworms and made a beneficial circle. The plants thrived off the fish waste and cleaned the water and fed the worms, the worms broke down solids into a more readily soluble plant feed, the worms fed the tilapia and crayfish, the crayfish kept the bottom tidy and occasionally small ones fed the tilapia. The tilapia provided waste to feed the plants.
Water changes were relatively easy for me and I used an IBC to collect water for water changes. IBC totes usually have a drain valve on the bottom but I would’t recommend using them as they are prone to becoming stuck open slightly and hard to get reseated. I had a drain in the floor so I just drained them into the floor grates.
The IBC totes are cheap and easy to find. They are very versatile, lightweight and strong. Make sure that you get ones with the ingredients being food safe or some similar product to avoid killing or poisoning your inhabitants. Craigslist and other similar resources often have then cheap, sometimes even free.
It’s a great way to keep and breed fish you would otherwise never have the opportunity to breed and brings your fish room status up a notch or two in the breeding department. It’s cheap, easy, and works very well for a beginner or more advanced hobbyist and breeder. If you want to move up the gallons you keep it’s a fast way to get up there.
