I've read a lot online about pH levels in products and how that can affect pigmentation but haven't really found any solid advice. Any suggestions would be greatly appreciated!
I would avoid using any products with high pH levels because they're known to often irritate the skin. A lot of people with oily skin will use high pH alkaline cleansers to combat the oil but it can end up ruining your skin. The right toners are used to balance our skins' pH so you can also just get a balancing toner and try out cleansers on your own to see what works for you.
Tony Moly The ChokChok green-tea serum has helped with my dark spots, I use it twice a day instead of moisturiser.
This URL is a bit spammy looking but the content is interesting.
BTW it says home remedies... And starts off with stuff like laser treatment
However, if you scroll down a bit, you get to the home remedies.
I have freckles and areas of hyperpigmentation, that's just my skin and genetics.
I wear sunscreen everyday (even if it's not sunny), the higher the SPF the better and don't forget to reapply. UV rays damage your skin barrier.
I would recommend vitamin C products and exfoliation at least 2x a week.
I would also recommend Krave Beauty products! Their Great Barrier Relief is a great product.
Products work differently for everyone, so I hope you find something that works for you!