i had a sump on my 50g once. it was super awesome. unfortunately when i moved and broke it down i had to take apart the plumbing in the overflow and the rubber gasket/o-ring/sealing piece now doesn't sit right and leaks. i've been to more plumbing supply stores than i can remember, and none of them carry anything even similar to what i need. so, no more sump.
hopefully you are on a well. adding chlorinated tap water directly to the filter is a really good way to kill all your bacterial colonies.when adding water back in i put the end of the pyhon into the filter when the water gets up over the end of the tubeand let em fill up and they start filtering againl