well i found a freshwater clam/muscle in the mississippi river last year around this time and decided to put it in my tank. i's gone from my 55 to my 20 to my 30 gallon tanks. well tonight i noticed it was open more then normal and took an arrow and tapped it and it didn't close. it was dead. not sure what happened but it lived for about a year in my tanks. i fed it powdered flake food all this time. has anyone ever had one that survived for longer? if i come across more i'd like to keep one or 2 again. i do have to say though my sunfish loved the fresh meaty meal. got to love having a fish that acts like a garbage disposal lol.