When Paul Zmoda noticed that I'd hope to find at Lowe's an acidic cleaner based on phosphoric acid, he suggested Coke! I checked...pH is 2.5...white vinegar is 3.5 and the pH scale is logarithmic, which means that Coke is 10 times more acidic than vinegar. You could not pay me to drink Coke but I'll buy some store brand to try as a weed killer. And the sugars would feed beneficial bacteria.