We have a 20 gallon saltwater that has been running for a little over a year now. We haven't had any real problems, just a suicidal clown that decided to jump out of the tank. We're moving into a new apartment and we will have this tank in our living room. We will be adding live rock in december and hope to create a mini reef. We are currently using a AquaClear 300 as our filter. I've been looking at some other filter methods. A sump looks like it would be fantastic, I could keep the heater in the sump and add a protien skimmer as well. I was looking at different options including drilling the tank for a bulkhead as well as an overflow. Does anyone have any experiences with "mini-sumps"?