Have a problem with hair algae that snails, aggressive water changes, and manual removal can’t touch? Try upping your magnesium. Many aquarium keepers have reported success with hair algae removal after increasing their magnesium to over 1500ppm levels. The magnesium is said to disrupt the life cycle of nuisance algae, so manual removal will have to still be implemented to some degree. Fortunately though, digging in your aquarium for ever last thread of algae won’t last near as long since it won’t be growing back as voraciously.