Good luck with that! I did my own research and crafted my own diet. There are plenty of resources on the internet, they are somewhat difficult to find for those with low functioning kidneys (and not on dialysis). One thing is for sure, the dieticians in the clinics don't understand diets for low functioning kidneys. They have plenty of suggestions if you are on dialysis, but low functioning kidneys are not their thing. And frankly, if you're even on dialysis but doing your best to preserve your residual function they can't help much. As an example, telling you to load up on animal-based protein (especially red meat) is not something that will help your residual function. That has been my experience, anyway.

@teachaero I think like @maxwell123 suggested, it is best to craft your own diet. I myself am stage 3B, with GFR at 32% right now. Because I also have gout and fibromyalgia, I crafted my own diet. Using resources from rsnhope.org , Mayo Clinic website, and American Kidney Foundation I've have figured out what works best for me. As I laughingly tell people good thing I like oatmeal and apples and cardboard! I do admit that I fall away from the diet every once in a while because total abstinence is a recipe for disaster for me. But I watch what I eat very closely. My husband is a kidney transplant recipient Oct 2016, so he is aware of dietary restrictions from his time on dialysis. He lovingly reminds me as he sees me head off track. In the end each person has to figure out what works best for them and be their own advocate.
Ginger