That amount of potassium is perfect t keep potassium from declining due to the increases in salinity from the sodium and chloride, and the subsequent need to occasionally lower salinity. I showed that here:
The concern with Dowflake now is that they leave more bromide in it than used to be in it in the past, but no ones really shown any issue with that and regular water changes will keep it in check. :)
Use a calculator for anhydrous calcium chloride as that is a largely anhydrous version (at least according to the MSDS). I'm not sure why they'd sell that for pools. Maybe it is an error.
If it gets warm on mixing with fresh water, use the anhydrous calculator.
If it does not get warm, use the hydrate (Dowflake)