I bet it should be fine, there was similar discussion in the past that Ca bind with so4, and it's insoluble and will precipitate. Or You might dose them in separate day.

Hi Gents,
Currently I am dosing PPS Pro for my 22g Tank (2 T5 Tubes, 2l DIY CO2). As I cannot get KNO3 in Singapore, I use CaNO3 instead. Since KNO3 is not used, potassium is mixing and what should i do for that?? I do dose K2SO4 as per PPS pro recipe. Do I need to dose additional ferts to get Potassium? Please help and thanks in advance .
Sorry I couldn't provide my water parameter as I do not have any kind of test kit.
I bet it should be fine, there was similar discussion in the past that Ca bind with so4, and it's insoluble and will precipitate. Or You might dose them in separate day.

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