Any comments or options on this product?

I was looking for a metal out product in the local pool store and came across this recently. I have never seem it before.

I've developed some stains this year which I'm looking to treat. It sounded like a simple product to use as the only requirement was a PH level between 7.5 and 7.8.

I have a 23K gallon gunite pool.

Here's the link to the product:
http://www.phoenixproductsco.com/ter..._Mineral-1.htm

Google didn't seem to find anything. New product?