Good update with the pictures. Have you checked for any bugs under the leaves?

If the pH is drifting lower, maybe there's something wrong with what's inside the DWC bucket...

Not a hydro expert, just trying to help...

-Lay
WeayLay Reviewed by WeayLay on . 5 weeks into flower and having issues. PLEASE HELP!! This is a DWC grow w/5 gallon buckets. I've had pretty good luck up until now. I recently discovered my PH meter needed calibration, my babies were @4.8ish for over a week. I immediately flushed and went back to the 1000ppm GH 3part they had before. I saw signs of nutrient burn instantly so 3 days later I flushed again and went down to 600ppm. It's been close to a week now and the leaves continue to spot,turn brown, and die. Nutrients continue to increase and PH is still drifting lower. The Rating: 5