I would like to setup a simple closed loop so that i can get rid of my HOB 's. I would like to get my water running from my glass aqaurium into a "sump" where i can put my HOB equipment. I would like a plan for a simple closed loop that can achieve this. I have a 50 gallon tank. I am also not certain how large a "sump" i should use for this type of aquarium.