I have a 275 gallon IBC fish tank, 4 IBC gravel beds (16" deep) and an IBC sump tank. The FT and sump are covered with shade cloth. I am using an EcoPlus Commercial 3 air pump in the FT, so it is getting plenty of air, I think. I figure there is 400 to 450 gallons of water total. The question is, should I have to be adding +/- 20 gallons of water daily? There are several minor leaks (slow drips),…