thailer
Well-known member
what do you have in the aerocloner water or soaking the root cubes in? is there any fertilizers? sometimes they put that in the cloning gel or solution you put in the water. when i get spots or burn marks on coty's, i've chalked it up to fresh mixed soil so maybe something similar is happening? you say the clones in the same aerocloner are doing fine but the seedlings are sharing it?? you mention EC is in check too so maybe try them with no fertilizers??