HI guys, I think i found the ways to cure hair algae.
First of all I think most of the people has read reading about keeping water free of PO4, nitrate and low nutrient, etc......
I also read all the above but hair algae still come and look for me, so prevention is not good enough will have to cure it, I tried plucking them every few days, very tiring job and the hair algae actually grow more. Hence I surf the net to see which animal actually it hair algae!!!!!
The answer is sea hare, but a lot mention they are not easy to keep and will die after a few days or when all algae is gone. So I tried my luck, and get the sea hare. Very effective worker, start plucking and eating hair algae the moment it go into the tank. But the plucking is not clean so that is where my black sea urchin and powder blue tang come in. Powder blue dun eat long hair algae but after the hair algae is trimmed, he will go and peck.
Hence my conclusion is to clear hair algae must have a package of cleaning crew, sea hare to trim the algae, sea urchin and tang to finish off the rest. For me, I feel hermit crab and snail is not useful for hair algae, and hermit crab will kill snail for shell.
Hoped the above information is useful and the best for people still fighting hair algae( our common enemy!!!!!!!!!!!!)