Difference in PPM, which one is correct?

[PoolDoc]

The main problem with strips is not letting them sit in the sample long enough. Aquacheck recommends 10 minutes. I know the LaMotte strips are fast strips but know nothing of their chemistry and have heard that they are more difficult to use than the slower AquaChek, which are actually chloride capillary titrators.

Does AquaCheck still recommend this? All I could find on their not-very-informative website last night was a mention of 4 - 5 minutes.

[waterbear]

Does AquaCheck still recommend this? All I could find on their not-very-informative website last night was a mention of 4 - 5 minutes.

http://www.aquachek.com/newspdfs/Pro...oSalt_rev3.pdf

[PoolDoc]

Ok, I've archived that. Do those instructions still apply to all current test strips?

Here's a copy, with my emphasis added:
A recent change in our manufacturing process may cause the gold/yellow completion band on top of strip not to turn dark to indicate that the test is complete as stated on product instructions. The intended chemical reaction still occurs and an accurate test result will register in no more than 10 minutes. The test reading will be accurate regardless of status of the gold/yellow band on top of strip.


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From AquaCheck newsletter, linked above:

Please be assured our test strips continue to be made under the highest quality controls and we apologize for the inconvenience.

Current instructions on both products read:

1. Fill a small vial with about one inch of pool/spa water.
2. Remove one strip from bottle and replace cap immediately.
3. Insert lower end of strip into water. Do NOT immerse yellow completion band at top of strip. Important: Keep top half of strip completely dry to get an accurate reading.
4. Leave strip in water unless test is complete (when yellow band turns dark, about 3-*-4 minutes.)
5. Obtain your salt concentration: note where top (highest point) of white peak falls on the number scale. Read top of peak to nearest 0.2 division. Locate the sodium chloride concentration next to that reading in table below.

Instruction changed for Lot # from 9349 to 0236:

1. Fill a small vial with about one inch of pool/spa water.
2. Remove one strip from bottle and replace cap immediately.
3. Insert lower end of strip into water. Do NOT immerse yellow completion band at top of strip.
Important: Keep top half of strip completely dry to get an accurate reading.
4. *Leave strip in water for 10 minutes and compare strip to chart for results.
5. Obtain your salt concentration: note where top (highest point) of white peak falls on the number scale. Read top of peak to nearest 0.2 division. Locate the sodium chloride concentration next to that reading in table below.

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[waterbear]

Ok, I've archived that. Do those instructions still apply to all current test strips?

Don't know but 5 discovered on my own thatn 5 minutes ofent ws not long enough for the liquid to travel to the top of the strip and turn the top dark with the older strips but when I gave it a full 10 minutes the srip would be on the money (at least pretty close in the ballpark) with a calibrated goldline (oakton) salt meter

[PoolDoc]

Don't know but 5 discovered on my own thatn 5 minutes ofent ws not long

Didja spill some bleach on your keyboard??

[waterbear]

Using the notebook and just not used to the small keyboard! That's what I get for perusing the board by the pool instead of soaking in the hot tub with a beverage!

[PoolDoc]

Yeah, I've got to get a iPad soon. About 15% of my users, are using one, and the percentage is climbing fast.

(Susan doesn't usually get excited about new tech -- she just sees $'s going down the drain -- but she'll get the iPad come fall, and she can think of a number of ways that one could help her as she moves among classrooms.)

[cjryan33]

So the Taylor Salt Water test kit came in and I was able to test the water last night. The Goldline system is reading 2700ppm and the test kit stated that I was at 2800ppm. It appears that my system is closer to the actual levels than the pool store. The said my levels were at 3100ppm. This makes me feel better.

[PoolDoc]

I'm glad it worked out for you . . . and a little surprised that the results are so close together. That does suggest that your actual salt level is somewhere between 2650 and 2850 ppm -- it may not seem like it, but that's a really high accuracy reading!

[waterbear]

Also realize taht the goldine precision is as high as 800 ppm so both your reading AND the pool store reading are in spec!