The hawkfish may very well eat some shrimp. Depending on his size. As far as a cleanup reccomendation I would go with nassarius snails. Then some red leg reef hermits, which will also eat algae. IME
they were very calm, and didn't kill my snails. They were however killed by my stone crabs that till this die im still trying to roundem all up for the blender. Anyways nassarius snails are great scavengers, and don't eat algae but eat dead material. So they will hastily eat any uneaten food, and supposidly they eat fish waste. I think 200-500 snails, and 20 red leg reef hermits will get the job done.