Hi,
Well, again, 36ppm of Ca++ and 4ppm of Mg++ are enormous amounts and these values are enough to last a lifetime. These are micronutrients so you only need microscopic amounts.
The only time you should even think about this is if you are using straight RO without remineralizing (which is a bad policy anyway) or if your local municipal water is too soft and you did not remineralize.
There is no possibility whatsoever of depletion of Calcium (Ca++).
High Ca++ levels in the cytoplasm of the plant would be extremely toxic, therefore, the plant develops some very restrictive Ca++ uptake mechanism to counter the threat.
Ca++ is very mobile within the leaf but it NEVER travels from the leaf. Over the life of the leaf Ca++ never becomes depleted but only ever accumulates. All of this is self regulating, so if plants are in a high Ca++ environment they simply restrict the Ca++ uptake, while if they are in a low Ca++ environment then the uptake restrictions are relaxed and then it's only a matter of time before sufficient levels of Ca++ accumulate.
So, as is typical of advice found in The Matrix, you are trying to solve a problem that does not exist, and in doing so could potentially cause many more problems than you would ever solve.
If I were you I would immediately forget about adding Ca++ and Mg++ (and definitely forget about adding it via ammonium salts) because you already have more Ca++ and Mg++ than you need, which also is absolutely fine. If you are experiencing a problem with plant health and if someone told you that you needed to add Ca++ and Mg++ then you should ignore that particular advice, as the root cause definitely lies elsewhere (most likely with CO2 faults).
Cheers,
