Those are DWC. Are the roots getting enough water ?
You may need to hand water a bit to keep the the roots from drying and help them look for water below. That's why we like the drip system, you can cut the drip altogether once the roots hit the water good.

What kind of water are you using ?
LOC NAR on probation Reviewed by LOC NAR on probation on . My babies are 2 weeks old and starting to yellow! HELP! My plants are about two weeks old now and they are starting to yellow a little bit, and I also have one thats not acting like its wanting to grow very well. I was wanting to wait two more days before I put them in the Hydroponic system and started feeding them. They were doing great until I transfered them to the rockwool. Now as the new lwaves come in the have a bit of a yellow tint to them. Please check out the pics and let me know what do I need to do? Rating: 5