My new growth today shows some brown. Nute issues...

2.2 EC (1100 PPM)? That feeding strength is for a plant flowering in full and a hungry one at that. For seedlings, use 0.5 EC (250 PPM) total, or your seedlings will burn.

Rockwool cubes just don’t hold enough air to get plenty of oxygen to the roots, and they tend to hold onto a lot of water and get waterlogged easily. Since Rockwool can hold a lot of water, it’s prone to “drowning” seeds I highly recommend using Rapid Rooters instead for your hydroponic application (or any grow setup), as they are much more user-friendly and tend to get far better germination rates. But since u started them in rockwool already let it dry out to moist slightly dry then water again.

If you’re really giving them all the nootz listed , yes it’s way too much ! 1100ppm is what is needed for a 10 weeks plant !

Hi @MichelangeloGrows! Yes you gave too much nutrients, your EC/PPM is way too high for such young babies. If you use tap water for hydro, I would recommend to switch to RO water, this will give you a better visibility on what's really into your solution. Now to save these babies asap, I would get rid of the current solution, empty the reservoir and start with a fresh basis, with a moderated EC. Start with 1/3 of the recommended doses, no more, and slowly increase week after week if the plants are healthy. Remember it's always easier to fix a slight deficiency than to recover from a toxicity! Finally, seedlings seem to grow slowly from the very first days, so I would try to raise the solution temperature, the rootzone might be too cold, the sweetspot is 18-22°C / 65-72°F. Hope this will help, let me know in the comments section if you need any further information. Happy growing! 👊

Could possibly be overnutrition for that specific plant. To be sure check ppm of your nutrition solution and also the ph. Without this information it is hard to tell what causes the problem. Your nutrition dosage seems good to me.