Help with Redish hair alge on sand!?!?

I think it is Syno alge (sorry spelling is off) it comes from high nitrates and phosphate.
Are you using a phosphate reactor and GFO?
Using a phosphate reactor and a few extra water changes should help clear it up.
Sand sifters normally won't touch it

I am running into the same problem right now too.
My extra large diamond golby that normal keeps the sand nice and white won't have anything to do with it either.

 

Does it look like slime with some whispey things coming off of it, or is it like hair algea but red? If its the first it could be cyano bacteria, which could be caused by excess 'trates and/or lack of flow. The later could be red turf algea, but I will have to let someone else chime in on that as I will have to research up on it.

 

I had the same problem, but my water tested out fine. I stepped up my water changes a little and pushed my skimmer to the wet side of skimming. I then just let it take its course.

Get your parameters back in check, use a turkey baster to keep it off and away from any of your corals, and just let it go threw its cycle. It may take a month or more but it will go away.
Just some ideas hope this will help!

 

Keep doing the water changes like you plan.
When was the last time you changed the media in the phosphate reactor, it could need to be replaced.

 

Water changes sound like a good plan. Have you double checked your source water lately? Silicates and other garbage in there can cause diatom blooms and feed cyano and the like.