So I had red bugs... now I have acro eating flatworms

I guess some survived the freshwater dip and squirt with a pipet. Resilient b***ards!
Anyways, I am hoping to nip this problem in the butt (the infected pieces are only frags), and am going to get a wrasse to try and eat them to help out with the problem. My question is what is the best species to do this?
I am leaning on a coris wrasse, but I hear they sleep in the sand. Do you think one would do ok in a bare bottom tank?