For tuna fish meals, I purchase Crown Prince Solid White Albacore Tuna--No Salt Added. An entire 6 ounce can has less than 80 mg sodium. And it's the best quality tuna I've ever eaten--better than Bumble Bee, or Chicken of the Sea, or any of those.
http://www.crownprince.com/cpnalbacore.htmWhile supermarkets may stock some Crown Prince products, I have been unable to find this particular Crown Prince product in my supermarket. So I order it online, and have it delivered to me. Alternatively, some supermarkets will do a special order if you ask them.
I highly recommend this brand to anyone who is looking for a solid white albacore tuna that is truly low in sodium.
[Disclaimer: I am NOT affiliated with Crown Prince in any way; I am just a satisfied customer.]