I have a Flame Hawk in my 125. He is a very cool fish to have. I do not have any cleaner shrimp with him, but I do have a Maroon clown, 2 Tangs, 6 chromis, 1 blue Damsel, 1 Dragon Wrass, and a manderine goby. The manderine is about the same size. It does not bother any of them. I even have snails, hermit crabs, and a sally light foot crab, and emerald crab. He just looks at them. When I introduced the damsel, he was being a little pissy towards the damsel. They hit each a few times, then all was good. It is cool because he sits right in front of you and stares at you. He acts like he always has to be the center of attention. He is like, don't worry I am right here. If I did not have one already I would buying one. I even wanted to add another, but found out they do like to be in pairs.
I have lr with mushrooms and polyops, and I think some spounges. It does not mess with it. I do feed ghost shrimp 1 every other week. He is a very good at catching them.
My thoughts only, I hope they help.
Shel