ControlD
Diamond Member
When the water needs to be specifically tailored for a sensitive species it is safest to start with distilled water. You add minerals but you start with distilled water so that you KNOW what is in it and how much. Duh. Hell, even Sea Monkeys include a water conditioner that you can add to distilled water.
Much easier and cheaper (and just as effective) to start with R/O. But, I guess someone needs to keep the DI water people in business.