New to the TFP and this forum, so "HI" first of all. I've been enjoying reading and learning what's here - excellent stuff!
My conundrum is this: I've recently purchased the TF100 test kit, and my wife and I have been carefully testing our pool water to get it back in balance after a lengthy vacation. I had been getting testing done at the local pool companies. Because I had been getting different advice from each of the different places, I decided to compare the test results between the various systems, so I took 4 samples at the same time and had them all tested within a 90 minute period (yes, I did a bunch of running around to pool companies that morning).
Here are the test results:
SunGuard: pH: 7.4, TA: 108, CH: 270, CYA: 75, FC: 0, CC: .3, TC: .3
Leslie's: pH: 7.6, TA: 160, CH: 180, CYA: 80, FC: 0, CC: 0, TC: 0
BioGuard: pH: 7.5, TA: 173, CH: 192, CYA: 117, FC: 0, CC: .3, TC: .3
TF100: pH: 7.4, TA: 220, CH: 325, CYA: 70, FC: .5, CC: .5, TC: 1.0
FC was zero (we clearly have combined chlorine, as we couldn't hold it overnight). All 4 tests were very close to each other.
pH tests were also comparable, yet the TF100 visual pH test seems somewhat subjective. Any recommendations on how to accurately determine pH?
TA and CH were all over the map. The TF100 give the highest readings of both by far. We did the tests 3 times to be sure we were exact in our measurements, drop sizes, etc., and kept getting the same results.
CYA is also pretty subjective. Even using the 50ppm sample pool water in the TF100 kit we could clearly still see the black dot at the 50ppm mark. Not sure how accurate our readings are when the black dot truly "disappears."
Any thoughts or ideas why the TA and CH are so widely divergent between the 4 tests, and why the TF100 is consistently so much higher than the rest?
Any other advice is greatly appreciated. We've had cloudy water since we got back, though we are finally able to hold chlorine. I'm running an overnight drop test again tonight to see how well it's holding (we're keeping our fingers crossed on this one .
Thanks for any insights you can provide. It's great to be a newbie on the forum.