test strips

I have a pack of test strips (hth) left over from last year and I have a small pack I received this year (aquacheck) with some chemicals I ordered on line.

I get different readings on each strip especially on the amount of chlorine in the pool. Is there a true life spam on the strips or is the sell by date, which is last year, a means of generating sales?

Don't know about life span, but that's why we always recommend drop-based testing. Strips, even brand new ones, can and will give wildly different readings. They will tell you if there's chlorine in the pool or if there's not (most of the time, anyway), but to actually accurately know how much you have, you need drop-based testing.

Janet

To me, strips are like the canary in the coal mine. If it's deep purple I know I have lots of chlorine. If it's pale yellow or white I know I have little or no chlorine. If the TC pad indicates less than the FC pad I am yet again reassured that the TC pad is worthless. pH pads usually indicate the pool is more acidic than it tests with the phenol red drop test. Better to keep an OTO/Phenol kit for your daily testing. My favorite is the Taylor K-1000. The Phenol red neutralizes chlorine so you get more accurate readings at higher FC levels, and the OTO goes to 5ppm. Ben used to include the K1000 in his test kit.

I use 3 levels of testing:
Daily I stick in a Hach Silver or LaMotte strip (all other brands are IMHO, worthless).
If the reading isn't purple or is at all ambiguous, I retest with my K1000, or just test with it and skip the strip.
Once a week I run the full set of tests with my K-2006 equivalent (same chems, different kit). Since I have a vinyl pool I only test CH 2x a season.

Carl

thanks to all for the info.