Powerhead to keep algae on the sand down?

[RFGymnast]

I have a redish (purple?) slimey/scummy algae that keeps settling on my sand in my biocube 28. I don't mind removing it when I do water changes ~weekly, but is there a way to keep it from settling and end up in the filters? I already have a fluvalU3 with the bottom outlet open, but it's not too close to the sand, and I have the stock overflow outlet pointed down, but it still ends up settling down near the back of the tank (where the current is super low). Any suggestions?

 

[EriksFish315]

Sounds like it could be cyano. So more flow would help out some.

 

[RFGymnast]

Ok, I was also told by my local reef store that turning off the lights and covering the glass for a few days really helps. Any thoughts on that?

 

[Garybrooke]

The way to get rid of cyno bacteria is to run some phosphate media. Ideally, use the media in a reactor, or you can put the media in a nylon bag that you can get at any LFS, wash off the residue, and put it in an area that gets the most water flow running through it. Also, cyno lives off of nitrates so make sure you nitrates are in check.