Try dropping the lights down about and inch or two, with your fan heat will not be an issue.

Weak light can cause yellowing, but yours are not stretching which is weird, normally when the light is defficient the seedlings stretch and fall over.

A real weak dose of nutrients will not hurt them at this stage, like 1/10 strength.
Hempsouth Reviewed by Hempsouth 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