I have a ten gallon tank cycling with 4 zebra danios, one of which is a short-fined "glowfish". I find if funny seeing the genetically altered and obviously different one is dominant and chasing the others around. though i know its due to the fact its faster than its long fin danio tank mates. i've always found it disgraceful that companies were injecting live fish with dye. i'm glad now they can satisfy the publics need for florescent fish without causing suffering on the animal.