Ok thanks Tiny. My plants are showing signs of slow growth and nute burn. I will empty and refill res. with less nutes. I have not changed res. on a weekly basis, trying to go bi-weekly. Tiny thanks for the info on ppm. I didn't know you count your waters ppm. I thought Marty was my mentor, well Tiny is up there in my book now. Thanks Bro!!! I just checked my ppm are up to 1300 and ph 6.7 unreal. ppm rose 200 in one day ph jumped from 5.8 to 6.7