algae problems on rockwool?

[xsailbox]

Im having a problem with algae growth on my rockwool. its exposed to a hps light 24/7 and this green growth is building on the top surface of the rockwool... anyone have any suggestions?

 

[Guest]

Algae thrives on moisture and heat/light and the rw cubes need a good drying out period after wetting,I'd switch to 18/6 for one thing and back off on the light use floros if you have them.There may be not a lot you can do at this point but next time use 18/6, weak light,and let the rw cubes dry out a bit before rewetting them

 

[Guest]

cover the top of the cube so it gets no light, or invest in some organocide

 

[MTF-Sandman]

Yup...just cover the cubes with some scrap panda film or another white plastic. No light = no algae.

 

[xsailbox]

what should I put to kill the algae already there?