It was in my 29 gallon tank, 13 watt flourescent light, 1 cory, 4 zebra danios, 5 tetras and MTS. Of course the hair algae was not only growing on the java moss but also on the plastic/silk plants so I took it out of there. I cleaned the fake plants and replaced them and have no more hair algae in that tank (that was a while ago). The infested java moss has been relegated to a large cup (with a couple MTS that went along for the ride). The cup is by a window. Both plant and algae are growing great, 'course I only want the java moss.