is the tank cycling? is it established. While removing it is always good if you can, it will probably come back unless you identify why its showing up. My 92 is finishing up its last stages of cycling, and i have some green hair algae groing. It was already established, and i added some new Dry Lace Rock, bam whole new cycle. I tested for amonia, trites and trates, Amonia 0, trites 0, trates 30. Did a few WC's and added some blue leg hermits. They are having a feast eating all that green algae. If your amonia and nitrites are 0, and trates under 40, u can safely add a few snails/hermits to knock out the algae.