PPM seems awful high for clones. They hardly need any nutes at all. Are these fresh cuttings or well-rooted clones? If they're fresh you should definitely use a humidity dome.
Maybe in theory, but I have yet to see an idea like yours(I've tried numerous other methods as well) move my hygrometer to an acceptable level. The only thing that does that is a humidifier.
No mystery, just a rule of thumb when I start giving nutes to a plant, particularly if I've never used the brand before. Going full-strength can mean burning your plants the first time out. Good thing about Foxfarm is that it's organic and won't burn your plants as much as chemical ferts. So...
First of all, I grow in hydro. 3 feedings a day and I have reached the point where my plants can handle the full dose(worked my way up from 1/4 strength. If you're growing in soil, start at 1/4 and see how they respond, then work your way up. Use the nutrients every other watering. Water when...
Hey, I'm cheap too. I got the 7 pack(germd all, but only kept 5 strongest) and I just vegged them a little longer and they filled out my space nicely. Don't forget to use the "420" coupon code for 10% off.