This is where the water goes after is drains through the grow beds and flows gently down the drain tube. It ends up in the holding tank before getting pumped back into the tank. The plants get food and the fish get clean water. Win WIn.
This is one section that can be used to accomodate any size system. The Food Machine uses 2 of these connected. You can connect to an outside rain capture or to an attached Mini System too.