Hi i have my betta in a 16gallon tank, few weeks ago i had to move my 3 albino cories in with him as they were eating all my elephant nose food. A few times i have caught them eating my bettas fins? It started during when they were spawning. My paras are ammonia 0 nitrite 0 nitrate 5. Anybody got any ideas to what is happening? I'm totally confused here.