What is this?

Ok... I have two GHS White widow and Cheese plants in a 10 gallon DWC. Been having a leaf edge curl problem mostly with the WW but a little on the cheese as well since the start. Its not that bad only on the biggest fan leaves and some undergrowth. I have them in a DWC with PLENTY of bubbly, 600ppm 3 2 1 GH nutes using RO water at 25 ppm. Temps are a steady 70 degrees with exaust and the fans, everything. The only problem I am having is the ph fluctuating, which is what I think might be the problem. The grow is not at my place so I can not change the PH but once or twice a day. It goes from 5.5 to about 6.3 in less than 12 hours. Could this be the culprit? They also look a bit light. I have grown before and never had a problem. Other than this, no other problems and growing fast as hell. Check em out

any idea any one

could possibly be pH and a bit of burn?

try this: https://www.rollitup.org/marijuana-plant-problems/118601-guide-plant-deficiencies.html

to much water or food. Flush and go to 1/2 what you are feeding .

to much water or food. Flush and go to 10% what you are feeding for 10 days than 50% of what you been feeding.

What you feeding and how much?.

woodsmaneh! said:

to much water or food. Flush and go to 1/2 what you are feeding .

Click to expand...

Its in water DWC, with alot of bubbles, more than enough. I have the PPMs at 600... No burns at at all, in fact a bit light... just the lowest fan leaves got a burned from some heat they went through in the beginning. I think its the Ph, but I havent found much info on this

Dry humidity maybe.

I think its from all the ph down I am adding. I going to just switch out the res tomorrow and mix the water with some tap to get it more stable. I am starting to get really sick of it