I was diagnosed with Stage 4 CKD four years ago due to severe oxylate damage (GFR 16/Creatinine 3.80). I drastically changed my diet and am now at 36.7/1.90 and Stage 3B. Everyone’s situation is different, but my experience is zucchini is fairly high in potassium, so you may consider that. As for water, I was initially advised by my Nephrologist to drink 4L a day. Then we found that diluted my sodium levels, so we backed it off to 3L a day. Hope this helps.