ACV vs white vinegar?

[SandbarATX]

I'm confused about vinegar. I love using ACV products like the dpHUE Apple Cider Vinegar Hair Rinse Shampoo Alternative for scalp health and removing product buildup. So then I wanted to use diluted ACV as a first & final rinse to help remove hard-water minerals and to help counteract alkaline tap water.

However, when I dilute ACV myself (not ACV in a product), it grosses me out to pour mucky mineral liquid all over my head. If I'm using vinegar as a final rinse on clean, detoxed hair, why would I then ADD brown gunk and hard minerals to my strands? EW. That doesn't make sense to me. But pretty much everything I look up is ACV, ACV, ACV... what am I missing here?

Anyhow, I decided to try white laundry vinegar that comes in a big cheap jug (distilled pickling vinegar). I diluted to about a pH of 4 on my test strips (maybe 2-3 tablespoons per liter). But after several uses, I'm worried that the browns in my salt & pepper hair are turning lighter and lighter by 1-2 levels. Does weak white vinegar lighten the hair, or is it just removing the nasty minerals I never realized were there? The silvers look fantastic, anyway. I'll never use purple shampoo again. But I don't want to literally lighten the brown hairs, just clarify & detox them.

As a final rinse, should I ditch the vinegar altogether if it's basically bleaching my hair? Or give the icky ACV mother water another try? I kindly request insight.