If you have a saltwater fish tank, what fish will you get first?

Many fish would actually get a habit of come toward you before the feeding or at least they think you are about to feed them. I have seen a guy with a goldfish pond, every time before the feeding he would do , and the goldfish would all come to him. So whenever you do , the goldfish would come to you too because it is a condition reflex. I tried it too without giving any food, the fish still came.