Red/brown hair algae. Params inside...

[ToddG]

I have a 120 thats been set up for about around 3 months. Went through the cycle and everything has been great.

But I started getting a reddish brown hair algae that I havent seen in my other tank (24 set up for a year or so). Very long and stringy. Grows even with great flow. I have 2 tunze 6000's. It grows down between my zoas, on the rocks, seems to grow most at the top of the tank with the most light exposure.


Parameters are as follows...

Calcium 450
Magnesium 1400
Alk 4.00
Phosphates 0
Nitrites 0
Nitrates 0
Ammonia 0
Temp 78-81

Lights - twin 250watt 14k dual ended Metal halides on for 7hours.
96 watts actinics on for 1.5 hours before MH's and half hour after. They shut off a few minutes after the MH kick on and a few minutes before they kick off.

Octopus 150 needle wheel skimmer. about 130 lbs of live rock. Deep sand bed. Had some cheato but it seems to waste away. Even under good lights.

2 fish. 30+ snails of various sizes/species. 20 blue legs. some peppermint shrimps, fire shrimp, and 1 cleaner shrimp.

I use RO/DI water for everything. I do not have a TDI meter. I will be getting one soon with my new ro/di unit. But mine is in good shape and should be fine.


I do 10% water changes per week. May go 8 or 9 days but for the most part it is 7 days or less.

Any ideas what it is caused from and how to get rid of it...??????

 

[bertoni]

Hair algae can be a problem. You might get some help from a phosphate reactor, or by growing and harvesting a macroalga like Chaetomorpha. Both approaches are aimed at outcompeting the pest for food. Some hand-harvesting might help.

Another approach is to try to reduce the nutrients put into the tank. That's mostly food, especially if your RO-DI is in shape. I invested in a TDS meter in the end, to be more sure on that front.