Goes to show you should take the advice of people that have done it dozens of times, regardless of what your directions say. NO NUTES. Why do I have to keep typing it?

I too enjoy 100% success in my DIY cheapo aerocloner. I don't use rapid rooters however. I take a cutting, dip it in powdered rooting hormone, and put it in the cloner. The solution in the cloner has a very small amount of B1, in my case SuperThrive. Most of the powder gets washed off, but some remains, which cannot help but be beneficial. Within 10 days there's usually 3 or 4 inches of big fluffy roots. I have the bubbles on 24 hours until the first signs of roots show up, then 5 minutes on, 45 off. Water level below the roots by 2 inches or so. Extremely low level of light, like one small fluorescent.

Also if they rot, temps may be too high. Good luck. Please send pictures.