I know a lot of you are using sponge or mesh prefiltered canisters on shrimp tanks, but have any of you set up a true overflow and sump system? What kind of overflow are you using? Drilled through back with sponge over the fitting? Bottom siphoning in a weir with a bunch of scrubby sponges around the pipe to keep the shrimplets in? Who cares they're just shrimp?