There's a reason they're called feeders :roll: Its acknowledged/anticipated they typically don't live to a ripe old age and certainly haven't been coddled. Its imperative to float the plastic bag they came in the troughs for 30 or so minutes to minimize temperature shock. Initial die off will be significantly more than you might anticipate so buy accordingly. Those that live will be survivalists, reduce algae, gobble up mosquito larvae and reproduce. For the fry to survive and minimize predator depredation (coons and herons, etc) on the resident population its wise to place a piece of pipe in the trough so they have an opportunity to hide/escape. And yes, given the opportunity they can grow quite large and remarkably colorful.