Just in case you go bigger, this filter system is awesome. I had 2 but now only use the overflow boxes for my 46 bowfront and now will be transferring to 75g. For aquariums up to 90 gallons, don't know if it will work on a small system but check it out on Amazon.Awesome, thanks! I pretty much figured regular fish wouldn't work. I love the idea of that shrimp so that's something and I was thinking about the rockwork for a perching goby if upper level fish were a no-go.
KollerCraft TOM RP90 Rapids Pro Filter with UV Sterilizer for Aquariums