Shrimp tanks are a blast, especially when people come by expecting there to be fish in them. I just dropped 3 dozen ghost shrimp in my quarantine tank to keep as food for my bigger fish and they totally cleaned up the algae problem that I had going rampant in there for months. My Amanos are decimating the algae in my river tank as well. If you are willing to feed shrimp to fish, then dropping a bunch of them in a community tank makes for a fun entertaining evening as well as you watch fish go bonkers for live food, probably for the first time in months or years. My wonders killifish gorged himself on ghost shrimp and still stalks the remaining survivors amongst the very dense tenellus.