red stuff on live sand

[team2jndd]

I think you mean at most but yeah you are feeding to often. Cyano isnt only caused by over feeding it also flourishes under old bulbs and low flow areas. This stuff is in my 10g tank right now which is finishing its cycle. I hate it. I try not to use the slime remover because its like 20 bucks for this tiny vial and because ive had a problem with it killing every bi-valve i put in the tank.

 

[renogaw]

can also try red slime remover. but try to fix the problems, don't run your lights for a day or two if you don't have anything that requires lights. stop feeding 2x a day, fish only need it max once per day, but some people feed only once per 3 days.
if all else fails, the two chemicals listed will kill it off, but you need to turn off your skimmer or it will get sucked out of the water.