Hi everyone- I bought a 17 lb bucket of calcium hardener and dumped it in my pool about two weeks ago, left the pump running overnight and water tested at 210 ppm, today I bought another bucket that looked much older and from the sticker that was on it, it seems like it was manufactured in 2009. Does calcium chloride have a shelf life or expiry date? after I poured the recent bucket into the water and had the pump running for about 7 hours I noticed no difference between my test about 2 weeks ago and today, the ppm was around 210-220. any thoughts?