I have some hair algae and for some reason I'll often see it clinging on to a coral like this alien eye chalice. It will sometimes get hung up on SPS corals too and they don't seem to like it being there. Any help identifying what it might be, and what to do to get rid of it?
Under daylight lighting it's typical green hair algae, but I do get some rid film on the top of the sand bed. I just receive 2 ORA pincushion urchins today from Algae Barn. They are awesome creatures. My system is 100 gallons. I see your tag line, how many urchins do you suggest for a 6 month old 100 gallon system?
Then its probably hair algae. Id reccomend 1 per 50 gallons. The natural reef has 2 per square meter in reef under control of algae iirc. Yes they are awesome! Mine get algse pellets once in a while when i feed the fish.