Ph up and down are concentrated so after dilution you really have nothing to worry about much like fertilizer of any kind to much can cause toxicity and leave, root and tissue damage.
Now I'm a hydro grower and the stability of the acids we use are important to prevent fluctuations. So acids such as citric acid from fruits and vinegar are not ideal since they break down easily. Rather nitric, phosphoric and sulfuric acids are a far better option.
In soil it's about getting your soil makeup right so you don't need to add acids or bases to you feed or at least as little as possible. Things like peat moss etc will do the buffering for you. Peat will lo
wer ph naturally.
In soiless (like coco) like hydr
o you want to stick to an acid that does not break down quickly just like hydro.
As for what mixes are proven in soil there are a lot of very knowledgeable people on here like
@oldskol4evr and many others that can more than likely help you out with that