Does kalkwasser ever go bad?

[kevindub]

I found 3 pounds of really old kalkwasser. I think they are from 4 to 5 years ago. It is in a plastic bucket that is sealed pretty well and the powder is still loose. No clumps. Do you think it's safe to use this kalkwasser or should I go buy a new batch?

 

[Anonymous]

It can degrade, esp if it was not sealed air tight, You can mix 2 teaspoons in a gallon of water and the pH should be a 12. The Ca should be fine, it is the alk that will drop over time.