As I put the net into the water, I see the shadows nervously swimming away. I push the net to the end of the tank and lift it to the surface. I can hear the water splashes, the vibration in my hands. As I pull the net towards me and finally see the fish, it is full of silverperch. The largest of them is over 300g and 35cm. It’s a very nice fish. On top of admiring the beautiful shape and colours of the fish, we can see the beautiful fins. After working for years in aquaculture I am used to see fish with damaged fins, and broken rays. Here the fish are showing intact fins. This is the result of a nice growth in good conditions and low density.

This fish is almost 4 years old. Silverperch are slow growers and they don’t grow in cold water. As soon as the temperature falls below 15C they significantly decrease their feed intake and wait for the warmest months. In Melbourne (Australia) the temperatures are cold in winter and that is the reason why this fish took 4 years to reach this size. In warmer conditions it would probably already be over 600g.

If you are in a “cold country” you will probably be interested to grow other species such as trouts which can reach plate size in a single year.

I release the silverperch in the fish tank and plunge the net for a second catch. Again I can feel the fish moving in the net. This time I got few silverperch plus an Australian native catfish “Tandanus tandanus” also known as eel tail catfish. This little fellow is very interesting in aquaponics. It’s a bottom feeder and thanks to his moustaches he can detect any food sitting in the bottom of the tank. It’s also a very social fish that can be mixed with other species as long as those ones are friendly as well. It’s a good eating fish that offers a tender and soft flesh. It can grow up to 2 kg and more if you give it the time. If you handle this type of fish, be careful as it has some spines into the fins and can easily go through your skin. If you want more information about this fish, see the video “Bottom cleaner fish”.

Welcome here! If you are new, you will probably be interested to discover Jonathan’s six steps to build and manage an Aquaponics system. Click here to access for free! Thanks and good reading 🙂