what is this and how do I get rid of it?

[Kolby’s Reef]

Help please and thanks

 

[lapin]

Its on the sand bed just suck it out

 

[Kolby’s Reef]

Its on the sand bed just suck it out

I do and it comes back

 

[WheatToast]

Doesn't this thread belong in the Nuisance Algae (including bacteria) forum?
#MODS

 

[GSM_OFS]

I assume that is nuisance cyanobacteria. Nuisance algae/ bacteria forum would have plenty of information for you on removal suggestions.