I personally don't think it is fine to genetically alter fish like that or any living creature for that matter. To me it's a little off putting to know that the fish in my tank was altered genetically to look "beautiful". It then begs the question why not genetically alter humans to be pure bread without any sickness etc in our genes, let’s have designer babies then. Why genetically alter a fish to test water parameters when we can use technology and/or chemical test kits? Someone is trying to make a buck out of these fish. What would people do if scientists managed to change the pigmentation of rats to any colour of your choice, his eyes, tail, everything the colour of your choice, would you run to the pet shop and buy an orange/red/green/whatever rat? Ask yourself the question, are you happy with genetically altered animals? What is a fish? Is not the body you occupy an animal with a brain?