I recently purchased a 15 gallon tank. In it I have 4 aquatic plants 8 whitecloud mountain minnows and 1 male betta (siamese fighting fish). Everything was going fine for about 4 days, the fish seemed to be getting along. There were no territorial behaviour amongst them, in fact the minnows would follow the betta around as if its part of their school. Today I came home from work and to my horror found the Beta has lost all of its tail (caudal fin) and he only has one pectoral fin functioning! Its a very sad sight to see, if you ever saw a fish amputee, my Betta is a poster fish for it. I have already moved the Betta on its own. Should I euthanize the Betta or see if it would survive? I've reserached before I put this two types of fishes together and most of them said that the white cloud are compatible with the Betta and that they are peacefull community fishes. I certainly wasn't expecting them to act like a bunch of pirranhas. So besides other shoaling fishes what other types of fish can I put with the White Clouds. I'm hinking of getting a few dwarf puffer fish , so in case the White clouds gets another idea of nipping they'll get a good surprise.