How to help damaged seedlings

I have started some seedlings in rockwool. Once they got into the system rockwool got too wet and the roots got damaged/drowned. I noticed they were not growing and saw what was happening so I removed them from rockwool and put two straight into hydroton and one into soil. Its day 11 now, and ones in dwc are showing a bit of progress (I'm seing some nice white roots form and second true leaf set is starting to show), but are growing very slowly compared to one I put into soil (it has 2 sets of nice fully developed leaves).

I'm runing 200 uS of nutes in RO water since 2 days ago (embrional leaves started yellowing so I figured it was time to give them some food) and it was just pH-ed water with some heisenberg tea before that. Ph is kept at 5.5 to 6.5, temp is about 66F. I have a 18W pump and 4 airstones that make a lot of bubbles, so botom of the 6 inch net pots are driping wet and rocks on top are always moist.

I'm now trying to figure out why are my dwc plants doing so bad compared to one in soil and what can I do to remedy that. Could it be that moist hydroton is not wet enough, or that they are not geting enough nutes? Would it perhaps be better if I raised the water level (its inch below the net pots now), so that the net pots and hydroton are submerged?

When you put a plant in the net pots for DWC, make SURE you make a bottom layer of hydroton first so that the rockwool/root cube is elevated slightly and not sitting directly on the bottom of the net pot. If you don't do this then your rockwool will contenually draw and soak up water which won't promote the roots to grow out at all. Until the roots reach down into water you need to hand water the rockwool/root cubes if they dry out(once a day or so). If you don't let the cube dry out somewhat then once again, you will not be promoting the roots to grow down and outwards into your bucket. You are giving them too much shit with the teas and nutes if their roots havent even reached the bucket water yet. Once your roots hit the water sufficiently you should use a 25% nute ph'd bucket.

Its hard to say anything for sure without seeing some pics, but those are my opinions FWIW.

Cubes were siting on more then a layer of hydroton, but still they got saturated. I don't know exactly why, people here talk about needing to hand water their plants, but my medium is constantly moist even on top of 6 inch net pot without any watering. Perhaps its because I've covered the lid with black plastic to prevent light leaks, so it can not evaporate, and the pump is creating a lot of bubbles. When I lift the lid, water always drips down from the hydroton at the botom.

I gave them some nutes (tenth of a recomended dose) as I'm afraid they could be near the end of their food reserves (embryo leaves starting to yellow). Its still much less then what the guy in soil is geting (and he is doing much better).

Ok, plants were not growing because they were kicking everything they had into roots. Literaly overnight I got from nothing to roots sticking into the water.

Tomorrow its second res change time. Since cotyledons are shrunken and begining to die I prepared a 275 uS nute solution. Is that a reasonable concentration for such a young plants?