I live in Central Florida and we have nice year-round weather for raising blue tilapia outdoors. I became interested in Aquaponics recently and I am using an IBC tote system of my own design. I am amazed at the plant growth and I am hooked. The fish are fun too.
OK, so anyone running an AP system knows that fish poo doesn’t float. It accumulates on the bottom of the tank and the water can get smelly. I have been cleaning my tank with a bilge pump that is connected to a hose. I gently push the pump around the bottom and pump the water into the grow bed. Also, I use a brick to hold the hose down on the grow bed. The bilge pump is connected to a deep cycle 12v battery that is charged by a 100 Watt solar array.
I visited a local pet shop and asked them what fish would help keep my tank clean and get along with blue tilapia. The owner suggested a Plecostomus.
They had a buy one get one free deal going on so I got two. He told me that Plecostomus need a PH of around 7 but my research showed that they could tolerate a PH of 6.2. As soon as I got home the new fish were properly acclimated to my tank.
The Plecostomus were smaller than the Tilapia. One of the Plecostomus was floating the next morning so I assumed that the Tilapia must have picked on it because it was smaller. After a few days, I never saw the other Plecostomus and have never seen it to this day. After a few weeks, I decided to try again but with lager Plecostomus that were much closer to the size of the tilapia. This worked because they have been doing fine for about three months now and growing larger.
In order to make sure the Plecostomus are getting enough to eat, I supplement the Tilapia’s feeding with organic romaine lettuce. They will eat the lettuce down to the spine and it ends up on the bottom of the tank where the Plecostomus finish it off.
Also, I cut up a peeled cucumber sliced in 1/8” cubes that sink to the bottom and they love that. I also have a small piece of driftwood that collects algae, so they eat that and the wood. That is all I feed them but they do eat the food that the Tilapia leave behind. I assume they are eating Tilapia poo too because there is a lot less of it.
The Plecostomus have made a huge difference in the cleanliness of the tank and the smell of the water. My Plecostomus are getting huge now. Both of them are at least 12″ to 13″ long. They seem to have gotten territorial and even a little aggressive toward the Tilapia. I know one thing, since they keep the tank so clean, you could not expect to breed other fish in the same tank.