Maybe bterzz or bendoslendo would like to explain to the class what thier scientific reasoning is here?
Go get a bottle of plain vinegar and add to the rez. A pH of 6 is a good number to hit..
seconded.Vinegar is good for the 20 minutes it takes to get to the store and back with legitimate pH down. It's a bad choice for maintenance.
Thirded? Vinegar is for pickles. You can make your own down solution by going to the autoparts store and buying some battery acid; its Sulfuric acid works great. I use a solution in water and it is fast with the added plus of no colors or unneeded crap and it's cheap. Or you can go buy some acidic water with food coloring and stabilizers added for $$$. Then when your done making or buying ph down go buy an RO system and the bottle will last for years...seconded.