I had a lot of life in my overflow,so I took the sponges out,hoping to get the guys down into the sump. From there,hopefully theyll take the ride back up into my tank.
I use a strainer in the bulkhead in the overflow box and a coarse filter pad on my drip plate in the sump. I scrub the strainer and change the pad weekly. I've never seen any life on either or in the sump, other than brownish particulate matter which may have very small life in it. Nothing very large seems to get past my overflow.
I keep my filter sponge on my overflow and clean it when I do a water change (2x a month). I have not noticed life in my sump..but I do have a few hermit crabs that live in there.
