That other post has some misleading info.
Distilled and RO will both become oxygenated if left to air-equilibrate. The level just depends on temperature.
Yellowed leaves DO get better if it's from a N deficiency and you correct it soon enough.
Pharma is right, use tap water unless a) you are in hydro and have reason to believe your tapwater sucks or b) your tap water is atrocious, too bad to even use in a compost grow, which is most forgiving