I am needing to buy 14-16 pounds of Cyanuric Acid and am wondering if anyone knows of a good place to get it from. Currently my only choice within 30 miles is the local Walmart that charges almost $13.00 for 4 pounds.

Why do I need so much? Fairly new IG plaster pool (odd shaped so not exactly sure of gallons but approx 30,000 gallons) with a SWG. Not showing any discernible CYA level and what little I had has been diluted with all the rain and necessary draining.