In human biology phosphoric acid lowers ph of the body. Are natural ph adjuster used in are bodies is Ca (calcium). I have tested the ph of coke before and the reading was 2.5. If to much phosphoric acid is taken calcium is drawn out of the bones in order to compensate for the lowered ph. It can lead to ostioperosis, more so in women. As far as plants go most fertilizer ions will lower ph although P takes the cake. I do not know why anyone would need to lower the ph of a fertilizer with a acid. Phosphorus is stored in the plants biochemistry easier then N or K and to ad more with out knowing what it is doing to your numbers can be harmfull in ways such as lockup. I am not saying do not use, just be aware it may cause P lockup and lower the ph more then may be needed. The higher the hydrogen consentration the lower the ph in the chemistry world. If one needs to adjust the ph down I would recommend citric acid but in most cases ph does not need to be brought down with anything except usable ions.

One love
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