you seriously dont think 400watts of cfls is enough light for those seedlings? they arent even actual plants yet, they are still in the sprout stage...im not wrong, ive been growing longer than youve been alive most likley. they are NOT yellow because of the lights, or not enough lights, i do know it can affect color, im not stupid, but that ISNT the reason here. it is what it is, im offering you advice, telling you why your plants are getting necrotic, take it or not, i dont care, but dont put out misinformation like those plants are yellow from light, or lack there of, ive grown bigger plants with less fluros than you had and my plants were always dark green and very healthy