So the first time I used soil, My seedling came out and looked healthy. I started to notice a white hair like mold growing on the top rim of the pot. 2 Days later, The Mold Killed My plant and I started over. Now I have like 5 seedlings, and I bought small pebbles to keep the mold from killing it . I put the pebbles over the soil and that seems to be working .is that okay? and My ph levels seem pretty good . anything I need to do any advise from anyone that I doing wrong