I've been growing for 7 years, and just last year, I had problems with cloning like I never had before. You never said what they look like when you lose them. When I had my problems, the stems would just collapse or bend over to the point where they die. I finally put a humidity gauge inside the dome and it showed 99%, that's too much. I think 80% is just fine, and don't forget that they can suffocate if the seal is too good around the dome. In other words you need to let some air in there, which was another mistake I made. The dome only needs to be there about 2 days. Haven't had any problems since I changed those factors. Do not put any root accelerators or anything in the water....which should be ph'd at around 5.5

Good luck
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