Honestly. I know this is not a new problem, and I have been combing through all the related posts and articles on the subject. But I'm really hoping someone has some other ideas on how to erradicate this stupid hair algae! Sorry for the upcoming long post. Here is what I have tried so far... ...plucking, sucking, weeding, scraping, scooping, prying, brushing, wiping, scrubbing, blasting ... ....as much as I can off every surface of the tank, rocks, powerheads, cords, returns, sand, and snail shells as I can possibly access with tweezers, hands, brushes, basters, siphons, nets, and blades. I've also attempted natural control with: ...starry blenny (died) lawnmower blenny (2 died) red legged hermits (don't touch it) mexican turbo snails (only 3 left) one spot foxface (doesn't touch it) diamond goby (really helps the sand) dragon goby (really tries, but can't grab much) extra chaeto in the fuge (well lit and trimmed weekly) 15-20% weekly water changes (RO/DI only, 0 TDS) decreased lighting schedule (8hrs actinics/4hrs MH in the middle, 8hrs total lighting).... ....but the algae seems to come back with a flourish, almost within hours. It has gotten very frustrating and time consuming to manually remove the stuff every three days and the poor little critters really can't keep up with it. I know the solution lies with identifying the actual souce of the algae, but nitrates are testing below 10, phosphates don't register on my tests (which I know can result from the algae consuming it almost as soon as it is produced). Here is what I am considering trying: ...pincushion urchin (not crazy about nibbled coral or falling rocks) sea hare (don't like the inky toxin thing) more turbos more hermits emerald crab (can't help with the glass) lettuce nudi raising magnesium (not currently testing for it) adding phosban (don't like chemicals if I can avoid it) changing all my bulbs (3x175w MH/1xVHO white/1xVHO blue, 6mo old) complete lighting outtage (temporary fix)... Does anyone have any success with the above mentioned methods? My LFS suggested that I empty my fuge, replace the DSB with Miracle Mud and ceramic, remove the chaeto, and add bio balls. I'd really prefer to keep my tank as natural as possible, and those all sound like artificial filtration methods. But.....I am almost willing to try anything to remove this stuff once and for all. :death: Temp ranges between 76-80*, all other params testing normal. I have had some turbos die, plus 2 blennies that I could not get out of the tank, so there are some nutrient contributions there. I feed mysis and emerald entree sparingly every 3 days and supplement with bits of seaweed sheets for my tang and foxface. It has been getting really bad over the last month or so, even crowding in on some of my corals. Today, we took out as much rock as possible, scrubbed every surface with various sized brushes, put them all back in, and did a 30% w/c right after. My skimmer, pump, return lines, and PHs were thuroughly scrubbed also. I adjusted the water flow away from the areas where the algae grew very thick, because I read that hair algae likes high flow areas. Broke one of my pipe organ corals in the process. :frustrat: Please...is there ANYTHING else I can be doing to close the salon doors for good in this tank?? I'm sorry for the rant, I'm just getting very frustrated.