I also have low sodium issues, and avoid foods high in potassium like mostly all fruits (except berries and the occasional salted green apple), coconut WATER (coconut milk, oil, and butter are fine), and spinach. When I do eat potatoes (sweet) or winter squashes I am sure to salt them really well.
They stumbled upon my RSWS (renal salt wasting syndrome they call it) when I was in the hospital. I was vomiting profusely and the doctor decided to give me a more potent saline drip due to all the electrolytes I was losing due to all the vomiting. I improved substantially, so they finally thought to check my aldosterone and kidneys. I had low aldosterone and overload of potassium in the kidneys so they prescribed Florinef and ordered me to eat a low potassium diet. They gave me the ACTH test and said adrenals were fine, but we all know what a crap shoot that test is. This was over a year ago.
Florinef was horrible. It made my ankles swell and made the skin on my face feel like it was burning. I took it for 3 weeks when I was first prescribed it and then stopped.
Starting a nutritional balancing program and consuming massive amounts of Sea Salt was what got it under control. At first I was doing the Celtic brand, but then was turned on to Hawaiian Bamboo Jade by Marie64. This is the best salt there is. I have not had any need for the Florinef since.
During times when my body is under more strain, I will stress dose the salt (take twice the amount I normally would). I also do this while menstruating, due to the heavy fluid loss.