If you add a damsel def remove it give it fir free to someone else there only like 5-10 bucks, but when they reach maturity they get super territorial. Personally with cured Rock you can add a clown their also on the hardier side . Like everyone said don't plan on fish for a couple months when you do want to add them you'll be ready then. Any questions just ask
O and by rottng food I mean food added and just left to decompose not actual rotted food lol that may not be good
cheers