Critical time, need feedback on yes/no on nutes

[scottcc5s]

add 1/4 str, they are crying for Nitrogen. To my knowledge 3 main things will cause yellowing, lack of N, PH off, and Heat.

Thanks, will do. FYI I have them on a heat matt (80 degrees), under florescent tubes and up to now using distilled water (5.5 to 5.8 PH).

Lose heat matt??