Ca test kit accuracy

[doctaq]

hi all

ive recently started testing and dosing for calcium and alkilinity

i have the api test kits for those and was wondering what you use to test and if youve ever tested your kit against others

 

i tested store bought water in the store and got 425 from an elos kit and tested about 480 at home with my api.

 

the second part of the api test kit for ca has you shake the bottle for ten seconds before you start dripping, but i take like up to a minute to get the full test done, do you think the solution settles during this time and i should be shaking the bottle between drops? compelling stuffs....