i am thinking about getting a crayfish/crayfishes in my 20g tank but i want to also get fish. i was wondering if a 4-6" uara from the LFS could go with the crayfish From the LFS.
You mean a Urau cichlid? They aren't always the easiest fish to take care of. I'd want a bigger tank to mix fish in if there are a few crays involved. If you go too mean with the fish they'll take out a cray when it moults.. Go too weak and the crays will get some extra dessert when the lights go out.
Agreed... I've never had Uaru before, but my dad had a pair that got ENOURMOUS. Things might be ok very-short term, as the Uaru seemed to be pretty live-and-let-live, but I assure you that the first time the cray got any ideas, would also be the last time.
Also, a 20g is too small for Uaru, my dad's were aboout 7in when he had to get rid of them. If you just HAVE to put something in with the cray, try something peaceful, fast, and high-swimming to maximize its chances of surviving.