Hi guys, I have a 29 gal. tank with 50 lbs of live rock, 25 lbs of livesand/crushed coral substrate. 3 small fish, a sea star, 15 reef crabs, 2 top snails. My tank is getting a ton of brown hair algae all over my live rock and the substrate. My specific gravity is 1.023, pH 8.4, ammonia-0, nitrIte-0, and nitrAte is around 20ppm. My temp is at 76.5, I am running a uv sterilizer, and have a cpr aquatics bak-pak skimmer. I only use R/o water ever. Two different LFS told me the brown algae is normal and not to worry about it, but I am worried that it could be possibly choking out my liverock. I am using a 55 watt compact flourescent light. I know the nitrAtes could be lower, so I am going to do another water change in a couple of days. Thanks in advance for any input.