My plants are about 2-3 weeks from harvest and are drinking alot. I have them in 4gal buckets (DWC).

I do nute changes once a week. But being this late in the game the plants are drinking the 3gals of water/nutes in only a few days.

My question is; when I add more water to the res. to keep the roots from drying out do I add another feeding mid week or just add pH'd water?