Anhydrous Citric Acid - Rust-Oleum Concrete Etch

[dclynds]

Hello TFPers,

I recently re-finished a concrete floor with a Rust-Oleum epoxy kit and it came with two 1-lb. bags of anhydrous citric acid for etching the concrete. Do you think I could use this product in lieu of ascorbic acid for removing metal stains? If so, would 2-lbs. be enough to treat 17,500 gallons?

Thanks,
Daniel

 

[JoyfulNoise]

You can but probably not a good idea. It’s more acidic than AA (drops the pH more) and it forms chloroform when it reacts with chlorine which can be sickening and irritating at high enough levels.

Stick with AA. Save the citric acid for candy making.