Hi John,

We used muratic acid applied with an acid sprayer (like an ordinary garden sprayer) to the panels laying flat on the ground prior to installation. You can also lightly spray with water before applying the acid to achieve a modeling effect. The amount of acid you apply will also create the modeling. After you spray the panels with acid and once you've achieved your desired etching spray the panels with baking soda and water. 1 box of baking soda per 5 gallons of water. And thoroughly rinse with water.

Thanks for asking!