my seedlings are growing too slow, need help!!

hi, im growing my two seedlings in rockwool cubes under 3 23w cfl lights at 6500k, they are coming onto two weeks old now, one with yellow tips, with a little brown on it, the cotyldons look like they are dying and a burn mark on the stem, i was using (vitalink plantstart seedling feed) with an ec of NPK: 2.0/1.15/2.3 ph 6.5, there was a gel like white residue on the rockwool but i think that was from leaving nutrient water out so i stopped using it after a week and started using de-ionised water at ph 6.0 to see if any change, residue stopped but growth is still slow, any help will be much appreciated, these are my first grows

Put them in medium and start feeding again.

what medium do you suggest? i have larger rockwool cubes to transplant??

Are you planning on growing them in soil/coco coir or a hydro system. They need something larger right now for the roots to grow. I would get them into soil in at least 1/2 gallon pots. Fox Farm Ocean forest is good stuff and you won't need nutrients for at least a month. It may burn the plants a little but they will be alright in the long run.

My seedlings allways get of to a slow start.

i was planning just to do a rockwool grow all the way and just feed them the nutrients they need, because it is a small indoor grow, i have two little cupboard converts a small one fro germ and 1st step of veg and the second larger space for 2nd step veg and flowering, no hydro system but would like to do it by hand

throw them in some soil so the roots don't get exposed to light

You are going to have issue's i believe if you try it your way. Are you ph'ing your water? rockwool usually tends to raise it.second they will need watered several times a day if you plan on doing it by hand .(it will only take missing watering them one time to possibly kill them.)My suggestion is go buy a timer and a cheap water pump if your going to insist on hydrr buy a air pump and a tote and try your hand at D.W.C. much much more forgiving.

that was my 666 post hell yeah lol!

Wet rockwool is only going to get you green algae, which gets you fungus gnats.

Check out "Flood and Drain", and "Deep Water Culture".
I find DWC, cheap and easy.

Good luck and have fun

by any chance would that be bubbleponics?

Kinda....
https://www.rollitup.org/hydroponics-aeroponics/26645-dwc-hydro-vs-bubbleponics.html

i see, you guys have been such a great help thank you