Green Hair Algae is really a broad term that covers hundreds of species of green simple filamentous algae. These species tend to be simple, fine in texture, and have few distinguishable features including no presence of roots. If you see roots, its not GHA. Green hair algae can be pulled easily by hand, and tooth brush scrubbed off the rock . This is easier to do if the rock is outside of the tank. If it is growing from the sand, scrape with the edge of a credit card and sift it out with a net.
In many cases , GHA forms in presence of excess of available nutrients, particularly the majors like phosphates and nitrates. After pulling by hand, some cleaner crew that will help with this are : Blue Leg hermits, Cerith snails, Chitons, Turbo grazer snails, Sea Hare, Conchs, Emerald Crabs, Urchins and a few astrea snails
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