Can Chlorine tablets go bad?

[bubbles]

Don't worry, I am just using them for new plaster start up, but am starting to wonder if they have gone bad. I have had 3 pucks in since a week ago today and added 2 more 2 days later and I am still getting the .5-1 reading when I test. I am adding liquid chlorine in as well ( started 3 days ago) but without much if any CYA in the pool right now, it evaporates pretty quickly. Seems I am putting 1 96 oz bottle in every day since to maintain around FC 3.
The bucket of pucks stayed closed in their container in our shed over the winter..it did get pretty nasty for here weather wise, but the shed door was closed and there was no direct contact with precip.
Thanks!

 

[duraleigh]

Post subject: Can Chlorine tablets go bad?

Probably not. While you don't give any clue as to the size of your pool, your FC loss sounds normal to me.

3 pucks in a normal size pool will not have much effect on FC or CYA. The liquid chlorine you put in is quickly consumed by the sun.

 

[Bama Rambler]

Without much CYA in there you're gonna lose whatever chlorine you're adding each day.
If my math is correct, you've only added 5 tabs in there. That's good for about 3ppm per day in a 15,000 gal pool and you've only added about 8 ppm CYA. You need to add more tabs and if they're in a floater you need to open it up a bit more.