Backyard Aquaponics
A place to discuss aquaponics

I just like to be able to have the tank set up so that the inlet into the tank circulates the water in a whirlpool action, moving solids to centre and then the tank is set up (in whichever way chosen) to immediately remove these solids to the grow beds. This can be extremely effective, with poo literally being removed within a couple of minutes of it coming out a fish's bum. The worms are then feasting on it almost immediately .

This does not work as well with a pump as it does with a central drain or similar arrangement - with the exception of pumps that have the suction part right around the outside of the pump (similar to sump pumps) with the pump being plonked in the middle of the tank and running continuously. Other pumps tend to contribute to build up of residue (being around the pump where the suction is not). Also, any other obstacles left in the tank will make the proces less efficient. For example, I have a bilge pump in my tank that turns on if the power goes off (it just pumps water up from the bottom and returns it to the tank with a splaching action for aeration). Some solids can build up around this, though they do naturally move throughout the day, but there is some loss of efficiency.