sakaspuds
Fish Crazy
infact thinking about it, you dont need an overflow on the top tank if the water from the lower tank gets sucked up from a certain height, say 20 mill from the top of the tank,
if the water dropped below this height in the lower tank, the pump wouldnt be able to suck any more water into the top tank, so the top one would never over flow
if the water dropped below this height in the lower tank, the pump wouldnt be able to suck any more water into the top tank, so the top one would never over flow