Great advice holly! Sounds like stuff i hear Patrick say all the time lol!.
For sea hare's, i know we do it, other stores might, we have a trade in process, for "used" sea hares, where once they clean the tank clear they can bring back the gremlin and we will give have the price back lol. It works great and i have one on a 8th tank. He eats everything, except my bryopsis lol.
Basically gremlin(sea hare) recycling.