Is this mold?

It's my first grow and my seedlings are doing very well except one (I think). On the top side of the rock wool cube and around the base of the stem the is a very thin layer of white. I'm pretty sure this is mold as just inside the cube the stem seems to be turning yellow/brown so I have put the seedling away from the others. Is there anything I can do or should I just remove it. Any help greatly appreciated!

Reedie.

cover the top of the rock wool with black plastic u can spray the fungis with peroxide and cover it also it will die just get some black plastic make a slice and wrap it around the stem and cover the wool

butter111 speaks the truth as well as having a lovely-assed avatar.

That's great, I'll try it out. And yes you're right email468 very lovely!