SuperThrive is brutal and can easily kill newly rooted clones, so its likely thats what did yours in if they didn't have roots. I don't water my clones at all, I just keep the dome moist. If you water whatever they are planted in (I use rockwool), the ends usually rot where the roots are supposed to grow. Plus, watering below soil won't do any good since there's nothing down there to water. You have to let the leaves work the magic until there are roots.
The above post is fictional and should in no way be taken as truth.
If I were to grow cannabis, I would only do so to supply myself and my close friends. Doing this would take myself and my friends out of harms way by knowing the source of our cannabis, as well as take hundreds of thousands of dollars off the black market annually. It would also lower the demand of black market cannabis, and would ultimately help keep cannabis out of the hands of minors.