Hair algae is usually green, I hope you don't have dinos
If it is algae, the clean up crew is sort of secondary no matter which animals you choose. You need to get your water in check so there's no fertilizer to grow the algae. And remove as much as you can yourself. And then some snails, urchins, crabs, etc. will eat little bits that pop up here and there. But it's not like there's some animal you can buy to take care of the problem if your water is dirty to start with.