I had a turtle once. I actually didn't have a filter, so I had to clean the water a lot. I caught him in a "creek" near my house, and kept him for a year or so. After that, I let him go back - I'm sure he was stoked abou that 8). What was fun was feeding him crawfish that I'd also catch at said "creek". I quote creek because it's more of a run-off in a large ditch (to prevent floods).