Anyone have wonky Salifert Ca test kit?

[marie]

I've long since come to the conclusion there is no such thing as an accurate test kit under $100.
The only thing I test for now is alk and even then I don't take down any actual numbers, just the position on the syringe, if there is more liquid left in the syringe it means I need to turn the reactor up, less liquid and the reactor gets turned down.
I use IO salt which is consistantly low in cal and MG so I add them to my make up water and assume all numbers stay even in relation to each other