Green Hair Algae


New member
I've had an out break of green hair algae, and it's hard to get under control. I will admit that I let my water quality get kinda bad before purchasing a new RO unit. I've been using the new RO unit for about 2 months now, it is putting out 0 TDS water, so the water quality is greatly improved. I had a TON of green hair algae...but it has improved. I hoped that with the frequent 2-3 week partial water changes that I would not see much new algae growth...but it is still growing...not nearly as fast...but still enough to be a pest. Any ideas on what I can do to get rid of it. In 10 years...this is this first time that I've had this problem. I tried sea hairs but they didn't want to go on the rock where my main problem is.
you can try sea hares, blenies, manual harving, what kind of skimmer you have?? can you get a small tang??
I've tried sea hares...they spent more time on the bottom than on the rock. I have a flamingi, sailfin, and a yellow tang...they graze a little but nothing major. My protein skimmer I've had for a while...I think it is run off of a rio 800. Seems to do the job...I wonder if a more powerful one is necessary?
check out your lfs or online store for marine S. A. T. Save in all tanks. A gallon runs about 70.00 and works great. They also sell smaller bottles. My hair algae was gone in less than 4 weeks. Still using the same gallon I bought over six months ago, for preventive maintenance once a month.
Do you have a lot of detritus in the sand or are you using crushed gravel as a substrate?

Was at the fish shop last night and of course they have a few dozen display tanks on the same water system. All of them were just fine except the one with the messy eaters--the bottom was covered with detritus. That was the only tank in the system with any hair algae at all and boy does it have plenty.

Phosban + blue leg hermits. Give it time. Since you didn't use RO for a while, there is probably phosphate build up in your rocks that will continue to feed the algae even after the water is cleaned up. It will take time to all come out. I probably took me 3 months or more to turn the tide.
I also noticed that my tangs (Blue and Yellow) would only eat hair algae as a last resort. I don't recommend starving the little guys, but cutting back a little on any seaweed you feed might encourage them to try the home-grown salad bar.
what is your bio load, and what kind of skimmer you have??, yeah i forgot about the mexican turbo snails, does things are good with that algae, and yes dont starve your tangs, just feed them a bit less
I tried marine SAT a while back...but didn't notice any change in the algae situation. I've never tried Phosban...anyone else have experience with this?
I tried marine SAT a while back...but didn't notice any change in the algae situation. I've never tried Phosban...anyone else have experience with this?
I have (2) 175 watt MH (14K) and (2) 96 watt compact fluorescent actinics on a 90 gallon tank. The actinics come on at 9 am and go off at 9:00 pm, the MH come on at 10 am and go off at 8 pm.
I have heard that a long spined black urchin - also called "blue eyed urchin" is a great hair algea eater. THey are also more nimble than the pencil or short spined types so they dont knock over rock/coral as much. Just be careful handling them = "ouch"- get one tha tis as small as poossible - they grow fast.
I don't use MH, so you may want to confirm with someone else...however, 10 hours may be a little too long from the MH. Maybe cutting the time to 8 hours would help cut the growth a little.
Urchins can eat the algae but it also strips coraline off your rock and mine ate little tubeworms off my rock too-- I had one knock some rock off my pile too.... beware of urchins.... I've tried a few different species and each is too destructive for me (although I do think urchins are cool animals)... never again unless I have a huge tank (several hundred gallons)