pH up is Potassium hydroxide, NaOH. pH down is Phosphoric acid, H3PO4. No carbon from either source. I'm not sure how you expect to get CO2 from that. You can get CO2 from adding acid to limestone (CaCO3) though.
White distilled or cider vinegar is a passable pH down but you will have to check much more often.
When did I ever use the word stupid or imply anything of the sort? We all go through the DIY phase before learning what you can and cannot improvise.