Green mold on rock wool cubes

[Torco]

i noticed some green stuff on 2 of my clones. i have never cloned before, i dont know what that stuff is, mold maybe. this green stuff is only on the tops of the rockwooll cubes.

 

[SmokeyMacPot]

It is most likly alge. Cover the light getting to the rockwool.

 

[NoDirtWeed4Me]

Or you can go to Walmart and they have an algae destoyer that is safe for plants and animals. It's in the pet area.