Mould on rockwool problem

i have recently notice some mould growing on top of my rockwool and on some of the hydroton around it. also some blackish material but im asuming its from the clay because at first i covered the top of the rockwool with it.

any ideas how can i prevent it?


thank you

I had the same issue, I used a serrated knife to remove the moldy layer.

Overwatering a common mistake every one expericens take out of cubs and plant in soil - if not take out of cube and then put in new one, or "scrape the mold off (would not fix problem) stop watering

If they're rooted good taking them out of the cube is not a good idea.

Tha's mostly algae, quite normal caused by the light, cut a paper plate in half with a hole in the center for the stem and cover your rockwool and hydroton, that's what I do and it works great.

Example:

That green algae is normal and won't hurt a thing. Like the above poster mentioned, you can cover the cubes if it bothers you. Mold I've never experienced (is that what that white stuff is on the one cube?), I would just say to let your cubes dry out more. I'm not sure if some h2o2 would help kill it off, maybe?

I have some with agley and there all doing fine, it doesn't seem to affect the plants Infact one of my best plants has got agley

I will admit that for the first few years of growing I never covered the rockwool and the algae never seemed to bother it, today I cover it just to be safe and most of all to avoid getting mold, tho I've never had it, guess it's just to be on the safe side.