I'm having the same issues with starting off seeds in rockwool. I dont think I'm going to be using it for seeds any more and just use it for cloning. MG seed starting soil is what I'll be using for seeds since it's cheap and it works.i used foxfarm for my first plant and is budding right now. for my other seeds i tried rockwool but most of them never got roots on the bottom and just died. so now im sticking with foxfarm soil. workd for me.