If we are talking hair algae then fish will get through it fastest; tangs are really good or dwarf angels. If you have a reef setup, the tang is the safer option as they rarely, if ever, nibble corals whereas the dwarf angels may. I found half shelled sea slugs to be really good at eating algae. Before the population explosion, in my tank, of them I had macros everywhere. Now I have none!! Turbos are good for hairy algae but rarely touch anything else but combine them with blue or red legged hermits and you have an algae eating platoon. Cowries will eat both hair and macros which is a plus but I think they grow quite big.
Regards