I have been keeping them for a little while now . . .they are very active and fun to watch, although admittedly drab looking. They will do well in almost any type of water . . .they are primarily freshwater although I've heard they can do well in brackish. They need to breathe air and will supposedly drown if not given enough space to breath air at the top of the tank . . .because of their partial dependance on air they can survive water conditions that would kill many other fish. I keep the water temp around 80 and they do real well. They are voracious eaters and will eat pretty much anything they swallow. Learned this the hard way when they swallowed two blind cave tetras that were each about half of their size, so be careful that what you put in with them is about the same size and can fend for themselves. The three I have bicker endlessly among each other too. Supposedly they grow to about 11 inches in the wild, though I've never seen them that big in captivity and mine are about 6 inches. well fitting tank top is important or they will jump out pretty quick . . .hope that helps