Green Hair Algae

[Matt]

We're battling a rather unnerving outbreak of GHA. So far, we've taken some steps as recommended by others on this board and elsewhere.

1) Skim wet; done. We're taking about a cup of green water out of the skimmer daily.
2) Reduce feeding; done. I'm actually worried for the fishies, but they are coping so far.
3) Test water; done. All parameters we can test for are nominal. Mg is a little low-normal, but everything else is OK.
4) Raise PH; done. We brought PH and Alk up to high-normal.
5) Manual cleanup; ongoing with weekly water changes (I might start another thread about that adventure). Huge amounts of GHA are manually removed every week. Daunting.
6) Compete; We bought some Chaeto, set up a 27W 6500PC bulb over the sump (27/7), and are growing that out. It has more than doubled in size, but the GHA doesn't seem to notice. We now have GHA in the sump too.
7) Reduce light; done. Shortened MH time to 6 hours daily.

This stuff is extremely aggressive, and is choking out some corals. Does anyone have any other tips? I've read that complete darkness is one option, but won't that also kill or heavily stress the corals?

Tips, suggestions, expert advice - all welcome.

Matt

[Quagmire]

Do you know how old your rock is? Maybe its packed with no3 and is fueling you GHA.Just a thougt.But if you want to check your rock,take some out of the tank and put it in a container of clean salt water,let it sit for a while.Maybe for a day or over night.Then test the water in the container for no3.
Or just keep doing what your doing,eventualy with good maint. it should all come together.

[niloc16]

try and find a sea hare from someone that you can borrow to help keep it in check until you can find the root problem. or you can buy one but once the algae is gone i would find a home for him quick.

[Beverly]

Sounds awful, Matt :(

I'll bet a lot of detritus is being trapped in the GHA. Try turkey basting it a couple of times a day to see how much gets into the water column. Hopefully your skimmer will remove it.

Also, you running a sandbed or BB? If a sandbed, when was the last time it was changed? Could be loads of nutrients in the sandbed. If running BB, are you able to get all the detritus out from under the rockwork to siphon it out? Most of the detritus in our BB settles under the back rocks under the powerheads. We use a turkey baster to blow it out to the back of the tank for siphoning.

[mark]

Totally guessing here, but are you checking for phosphates (and your test kits not expired).

[G1GY]

Phosban reactor helped me with this same problem. :)

[BCOrchidGuy]

Mark hit upon a very good point, try to get your water parameters verified by either another hobbiest or a LFS. Test kits can go funny even if they haven't expired, stick with a quality kit, I've used SeaChem and liked them although the Mg test was mind bogglingly complex. I'm using Salifert right now and like them very much. Hagen and Tetra both gave me problems in the past and I lost my trust in them.
You've either got a nitrate problem or a phosphate problem if it's nutrient, if your light is old or running very very yellow it will be a big contributor as well.
The other thing you could do if your tank is established is to move the livestock to either another tank or to containers, mix up a 100% water change in some clean garbage cans (plastic) and then drain the aquarium and refill it, take your time getting the livestock used to the new water chemistry and then do regular weekly water changes until the GHA is allllllllllll gone.
Final tip from me, a fox face and a tang can eat a lot of algae and make the job go much quicker.

Doug