Any idea what this is? Just grows on sand

[William Mumford]

Probably going to get killed for this suggestion. But 1ml to every gallon of water of hydrogen peroxide will most likely rid you of that problem. I had a similar issue and used peroxide for a week or so and it helped like crazy. All of my sand was that color and most of my rock. Now none of my sand is that color and tiny parts on my rock have a little spot here and there. I dont like dosing anything to my tank but this did the trick and I see anything negative happen as a result.

 

[brandon429]

Agreed that can work it’s powerful. Lysmata shrimp must be factored as sensitive likely loss where applicable. Pretty much anything shy of lysmata are tolerant

 

[brandon429]

We rinse it in tap if you can believe it ~ just because unending supply/rinse to perfection all target and feed evacuated. No recycle happens if the rinse is thorough, partial work is the ironic risk