Expired Test Kit- What Happens?


Active member
Jul 27, 2017
New Jersey
Hi TFP. I have the Taylor K-2006 and Sodium Chloride K-1766 test kits, but the bottles have expiration dates ranging through 2017-2018. I’ve already put in an order for new kits but they won’t come until next week. I just opened my pool 2 days ago and it was a little green, so I’ve been adding liquid chlorine daily & testing to at least keep the FC around 8 until I can get my new kit.

My question is what happens when they’re expired? Like would you know for sure because you didn’t get any reading at all, or is it biased lower or higher?

For example, my FC test seems to be working as expected, i add 1/2 bottle of bleach to get it to 8 then the next day it reads around 3-5, assuming its working to eat the algae. (After 1 day of this the water was pretty much sparkling clear, so it’s not a bad problem)

But the low salt light is on my SWG so I just tried to use my old salt test kit and even though I added 75! drops it never turned from yellow to red.

Can I assume the chlorine is probably mostly accurate and the salt is just totally wrong because it’s expired? Or might the chlorine also be totally off even though it seems to work?


Bronze Supporter
Jul 6, 2017
Kinston, NC
I bet your FC test is OK if the colors are changing as expected Just do manual additions until your salt test reagents arrive. SLAM if FC consumption is excessive.
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