I'm not sure what to say about your clones, as I have no experience with rockwool. I do all my cloning in Jiffy pellets, and pH problems can be an issue in both. Are you keeping them in a humidity dome? If they're fresh, you want to keep the humidity very high for at least the first week. Also, cutting the larger leaves in half really helps to cut down on transpiration, and seems to help them retain their turgidity.

As for the rest, fill out the Troubleshooting form and post your conditions. You'll be able to get more tailored answers that way.

Take care. :jointsmile: