Will CO2 indicator liquid expire, i.e. turn bad & inaccurate?

[ralliart12]

Hi fellows, may I check with you that will those CO2 indicator liquid/solution, i.e. those from CAL & Gush, expire & turn bad (hence rendering them inaccurate) after being stored for a long time, say ~3 months (in a fridge)?

[felix_fx2]

Answer is no. Unless have other thing mix and effect the kh value.