This is what I do, and it works very well. I have done many tests. I use 6" netpots. My medium is half rockwool (cut up or precut in small 1cm cubes) and half hydroton (clay pellets) mixed evenly. When the clone is ready with good white roots popping out, put it halway down in the pot, leaving about an inch below the clone. Dip the whole pot in PH balanced water (5.5-6) that has very light nutes and a couple drops of superthrive. Do this every day until roots start to pop out the bottom of the netpot. Continue to dip the pots daily (dont worry about overwatering, the clay pelets keep the roots from rotting) pinch the roots that are coming out of the netpots for the next week. This promotes more root growth in the 6 " pot and in a week you will see many many more roots coming out of the pot. They will need to be trimmed daily or every other day. At this point you can put the pot over some water with the bottom of the pot about two to three inches from the bubbling water ( i use tupperwares and get 4 in each tupperware) Add some vegging nutes (1/4) strength or about 250 ppm), PH balance your water, and sit back. Once the roots have grown down a bit you will want to drop the level of the water to about 6-8 " below the cups. Try to trim the roots as they drop so they grow into the water evenly. this way the root ball is more even and profuse. The biggest problem i had first doing this system was dropping the water level. you dont want the roots to be in water completely as they need air and will rot if you dont give them air. Good luck!