I have a 5 gallon tank that was my fry tank. Well I'm tired of all my guppy and molly fry so I was considering maybe turning it in to a saltwater tank for just a small clown fish. i have a 3 year old that is dying for one of those thanks to finding nemo. So what would I need to do to pull this off. I don't know the first thing about saltwater tanks. could I just add something to the water. Your help is greatly appriciated. Thanks