I have two couple month old Comet Goldfish in 20 gallon tank. (Won then at a carnival in early October and Its May) They currently eat Goldfish floating pellets. I'm thinking of switching them to bloodworms and brine shrimp because I heard those were healthier and better than Pellets. However, I don't know how much would be a good amount to feed them or how often I should feed them once I switch them. Ad if I do decide to switch them to that then is there anything else I should add to their diet or would that be healthy enough?