Help Needed
 

I have just started to tiny patches of hair algea on my rock. The good thing its where I have no corals. My tank consist of mainly sps and clams. Cutiing down on light time is proably not a good idea. How can I get rid of it before it spreads? My tank 29g, flow 2 korolias #2, 2 powersweeps 160gph, I have a skimmer and a powerfilter. Params- CA-450, Alk-3.5, Mag-1250, Ammonia,nitrtite both zero, Nitrate less than 10. Any help is greatly appreciated.

Have you tested Phosphate? What kind of make up water do you use?

My guess is Nitrates or phosphates, If you are using ro/di water check your TDS .

I use ro/di water and according to my test kit phosphates are 0 and nitrates less than 10. I started to notice these patches when I started feeding Dts plankton. Any ideas if that could be the cause?

Phosphate tests can be tricky. A lot of the times they aren't that accurate. A "zero" reading just means that phosphate is lower than the tests range. Unless of coarse you are using a colorimeter or a digital titrator.
Another way to look at it is you have algae in the tank taking it out as fast as it gets put in. You aren't going to record nutrient levels until there is an imbalance.
I had the same problem with DT's, try feeding half as much

DT's is a nutrient-rich food, IME can easily lead to nutrient imbalances.

I'd cut down on it's feeding significantly, and after a period of stability, very slowly increase it as you watch how well the tank handles the nutrient addition.

As mentioned above, getting PO4 readings off a test kit can often give a reading of zero despite nutrient/phosphate issues. Colorimeters give much more specific results at low levels and often lead to more clarity on the issue .... though often just following through on improved export and nutrient control solves the problem.


What kind of powerfilter? What kind of media/etc in there? Is it something that could trap detritus ala most mechanical filters?

I'd be sure to keep that clean, keep up on tank maintenance, perhaps up your w/c schedule for a bit, and keep that skimmer clean and tweaked. Drop the feedings [esp of DT's and anything other than fish-targeted] and let the algae disappear.
Then up the feedings a little, watch over 4-6 weeks to see if any nutrient issues develop. If not, then consider feeding a little more and repeat waiting/observation period.

Just my opinion, though .... and IMO, the more opinions, the better.

MiddletonMark- I use a penguin 350 in the 2 media baskets there is carbon from marineland and the filter cartridges. Good advice I'll try cutting down on feedings and stop dt's for awhile. I currentky do w/c every week and half. Thanks for all the great advice.