Lawnmowers and their close relatives the bicolor blenny are both great at eating hair algae.(and caulerpa trust me on that!) I had a bicolor once and it really was one of my fav. fish. Unfortunately, my heater broke and electrcuted all the fish in that tank but, while he lasted he was awesome. A great algae eater. Mine also ate brine shrimp and formule 1+2. Good luck!