tiny whit dots on top of rockwool

[941Seamus]

These white dots are appearing on top of my rockwool. It started after algae appeared on the top. Does anyone know what it i

 

[gagjababy]

probably mold. Cover the exposed rockwool from light, also use hydrogen peroxide to kill the existing stuff I'm not sure of the amounts...

 

[SativaWeed]

It's probably mold, or it could be salts leaching out, either way, peroxide,flush it with distilled water, cover the slabs with WHITE plastic to discourage more mold. Should be controlable after that. Good luck and be safe.