you could always spot feed ur future fire shrimp if you decide to get one. I have a 75 with a fire shrimp and try not to overfeed my fish. So next to no food falls down for the shrimps. So when i feed my anemones some shrimp, i cut up some rice sized pieces for the fire shrimp, and my coral banded. My cleaner shrimp is smarter and hangs out by my overflow during feeding time and grabs any food that floats towards the overflow so i don't worry about that guy.
Quick update on the fire shrimp situation...being a beginner..I wasn't aware that you also need some fresh water to balance out all of the salt. I was topping off my tank with saltwater and so MCF speculates that's what did the shrimp in. Now I know!
Glad you figured this out.Like I said in post above check your salinity.