Roots with mold

I grow hydro with grow cubes a few of my plants that I have in veg 18/6have mold on the root
what causes this and how do I stop it :confused:

http://boards.cannabis.com/forumdisplay.php?f=23

Thats the link to the hydro forum.

You can also try the forums search engine for 'mold'. I've never had mold, so I don't have the answer other than pointing you in the ponics direction.

good luck