We had a Halloween Crab when we first started our Nano Tank and between he and the electric blue hermit crab they cleaned the tank out of hair algae, and all green or brown algae in the recently cycled tank. You might try searching for a halloween crab to borrow for a week or so. They had the 24G clean as a whistle in just 2 days and none of the hair algae returned. (What we have now came in with different live rock introduced into the tank.) The halloween crab has the dark and light orange stripes and likes the narrow opening shells. Good luck!