I currently have a 4 day old (from sprout) seedling growing in DWC. It is in a root riot cube surrounded by Hydroton clay pebbles. I am hand watering atm with no water in the bucket as my last seedling is in very bad shape from having my pump on as it was over-watered by the bubbles spitting water up at the net pot. It was stunted massively and the lower leaves died completely along with the roots going hair thin and brown at the tips. My question is, how long should i hand water it before adding water to the bucket again? Also, I am just worried because i saw some slight thin brown roots again (just the tips) yesterday poking through the bottom of the net pot, i have since removed them (was very slight) and things seem fine for the moment. What is causing the thin brown roots? I believe it is probably too much water but i have been quite careful and only give it a few drops when i see the cube has dried out. I have read a lot that says when the roots are showing through i should have the net pot just touching the water, but i fear i will over-water it again with this method. Any help is much appreciated as this is my first grow.