I have been having a hair algae issue in my frag tank. This is how I plan to tackle it. I am getting a herbevorous fish, such as a yellow tang. I can't find a small one at the moment so I sm going to get a blotched rabbit fish. Be careful of their venomous spines, this fish is not recommended for beginners. This fish will get rid of hair algae above the egg crate. I will then proceed to get some lettuce nudibranches for below the egg crate. These will definitely clean up below because hair algae is their main diet. You can also try some snails, such as astreas, strombus, and turbos. I can not get snails because my tank is rimless and the snails will crawl out of the tank. This is my plan to get rid of hair algae, and if you have an outbreak, here is an idea of how to take care of it.