green star polyps vs algae

Attached is a pic of what is usually a beautiful expanse of green star polyps...picture, if you will, their brilliant green tentacles swaying in the current like meadow grass in the wind...NOT totally retracted and covered w/ this nasty red stuff.
Is it cyano? And, other than a toothbrush, how do i get rid of it?

 

lack of water circulation and Dissolved oxyen levels may be low or High DOCs and its a little hard to tell for sure but the water looks a tad yellow to me in this poto.. You us carbon and run a good skimmer ? Oh I just saw the 3 inch of sand bed ): may want to either add another inch or two or remove 2inches ? But at the age of this sand you may still find the problem in the other areas first. At just 3 inches its not fish or foul just more of a problem.

 

Thanks, Tangster. I did have to change my flow patterns a few weeks ago. Hopefully they'll get back to good when I get the SCWD going later this week. And hopefully the fuge I'm setting up with the Wally World kitty litter (at your suggestion) will make up for the barely adequate sand bed.
I'm running a Remora so I'd think that my skimmer would be okay and that my DO levels would be okay. Hmmm...
All the equipment is going to get a good cleaning when I move the tank to the new stand and hook up the sump and SCWD. Hopefully after that things will improve. I'll let y'all know...

 

Toothbrush and / or a turkey baster. I find that my GSP seems to collect detrius, and eventually, cyano will pop up when it's retracted.