Phosphoric Acid 85% - High Purity Industrial Grade - Premium Multi-Purpose Use for Cleaning, Etching, Rust Removal, and More. (500mL)

Came in 4 quarts instead of a gallon but that just made it easier for me to not have a full gallon open. But I only need about a pint at a time for dilution to 25%

Took care of nasty bathroom rings

Good buy

I have used 85% Phosphoric Acid for brewing water pH adjustment for many years. The water I use for brewing is around a pH of 8. I use a little under a tablespoon to adjust the pH from 8 to 5.2-5.3. The typical 10% phosphoric acid solution you can buy in most homebrew shops would last for two brewing sessions. This is a great product for brewing water pH adjustments. If you use it, be extremely careful because this strength will "burn" you, your floors, counters, carpet and anything that is not acid resistant. Wear safety glasses to protect your eyes. If used properly and safely this is a great product for brewing water adjustment.

Ok

Does not remove rust as quickly as some I bought from Western Auto years.

I am satisfied the product works well. I raised the ph in well water I use to water individual plants in five gallon buckets. Be very sure to boy the ph tape and see what you are getting. You can easily over do this stuff because it is so concentrated. The cool thing is that while it raises ph in the water, it also adds phosphate to encourage root growth and flowering.

A low flavor efficient pH reducer, used in making wine. At work I had reagent grade phosphoric, good to find a source for use in the winery.