(might be OT for 3reef, but on-topic for RO/DI, and I like 3reef's sponsors!;D) Last week I read an article about TDS in the local water, and what those TDS are made up of, then I compounded this mistake by reviewing the research behind the article... and have been hiding under the bed since. YIKES! What moron said this stuff is safe to drink! EEP! Anyway, when I'm not entertaining my fish (I think they watch me as much as I watch them), I'm baking, so I need some beneficial TDS after removing the garbage in my water (chloroform, arsenic, and cyanide were the ones I was familiar with, the others, less pronounceable, probably make those tame by comparison). Bakers are best off with slightly acidic water, and 50-150TDS (though we'd like to avoid poison in achieving the TDS). So once I remove the garbage, are there products out there that can add small amounts of beneficial TDS in a controllable manner, and maybe some citric acid for PH?