How to clean algae on sand?

[meese-a-mew]

I have algae on my sand and I can't use my gravel vaccum to pick it up.
Is this even normal? But how do I clean it?

 

[Rivercats]

That's not algae but cyanobacteria. The best and most effective way to eradicate it from your tank is to get Erythromycin and do a 5 day treatment since it is bacteria. Many people like to use Maracyn.

 

[Rivercats]

Should have also told you Erythromycin will not kill BB and if you vacuum as much of it as possible off the substrate before you start treating you may not even have an ammonia spike which can happen from the dying bacteria.