I just use 3 (9 volt) batteries in distilled water. Been making it for over a decade, never a problem. True about the pale yellow color, is best at that PPM. Don't let the alligator clips touch the water, they will contaminate the mix with the bad metals they are made of (no need to colloidal the clips!), Very safe, will get rid lots of different bacteria, viruses. Natural antibiotic. That's why hospitals use it in various forms. There's a lot of misinformation out there, maybe lots of trolls on this subject.