I've had a 20 gallon sw set up for two years now. I hadn't had any problems until about three months ago. I started to get these clumps of green algae that look like patches of hair about an inch long growing all over my live rock and inlet/outlet hoses. I tried brushing them off with a fine toothbrush, siphoning the larger clumps out, and using a fine foam over in outlet to catch the left overs. I pull the foam out when it gets covered with the loose algae. I'm running a fluval 305 with everything in it...including phosphate pad, a sea-clone 100 protein skimmer, and two powerheads. I only have a few small fish and several snails and hermits and only feed them two small pinches a day. With out fail, within a week of cleaning and partial water changes (I have a reverse osmosis/DI filter for the water) the clumps just start growing back. What to do?????