Calibration solutions now discontinued, use the more accurate “tank water method” for calibration
$23 for 2 month supply, $43 for 4 month supply, $59 for 6 month supply
We do ship outside the USA, but ONLY the "JUST ADD WATER" kits
Calibration solutions to be discontinued when current supplies run out. The most accurate way to calibrate is to use your tank water, and input the values of your tank
