Had a crayfish in my tank for a while, but had to get him out after he climbed on top of the powerhead and became readily noticeable to my fish, who decided it would be nice to eat his eyes...he's gotten at least one good one back from molting, but now resides in his own tank. I plan on having a polypterus delhezi in my tank with my new africans I'm getting, he was fine with the Green Terror, firemouth and convict I had before, he has thick scales and hard to get eyeballs lol. hopefully he doesn't see them as snacks however. If anything, try a batch of syno. cats, I hear they're a ton of fun, I might pick some up to try them out.