I just got my Bluefin Killis today and have them in a 10 gallon tank outside in the shade. But I do have lights (LED) on them for the plants. I'll run those lights for a few hours in the evening to help the frogbit grow. There are six of the killis. They look very pale and somewhat yellowish, but the blue fins are starting to show. After they get acclimated I hope they get good color. I put a tub over the top since they are known to jump, and it works to catch the flies and mosquitoes at night with the LED's lighting it up. They are wild caught so they need the bugs while I get them used to flake foods. But they did eat frozen brine shrimp and bloodworms today without any hesitation.