soil flushing, leeching

i have 6 plants that are 3 wks into veg under 400 mh and are about 2 feet tall. ive been feeding them foxfarm grow big from day one and i am concerned about flushing before transplanting them to 3 gallon containers so theres no lock up or over feeding. i also think my plants roots are root bound because theyre not bigger and theyre in containers less than a gallon. next time theyll be in bigger containers. and can i use the garden hose to do the flushing or should i use pureified water? another thing, is it better to transplant dry soil, wet, or damp?

Always Stand Water, Dont Use Straight From Tap, I Keep My Water Up In A Dustbin Were I Also Add Nutes, So The Consistency Of Water And Nutes, Are Always The Same Unless You Need To Add More Food Ect, Have You Got Any Pebbles In The Bottom Of Your Pots.
Craige...

you know, i was going to do that but i just used ocean forest because the guy at the garden store said that was all i needed.