I recently upgraded to a Palintest 7100 Photometer, from a Lovibond Comparator and various other additional test items, so out of sheer curiosity I did a full test of all of a pools parameters using all the equipment I have available for testing pool water with, it did crop up some interesting results:
The test strips aren't that old, a customer had them when I started doing their pool, so instead of binning them they have just been cluttering up my testing case, but certainly gives good evidence that test strips are horrendously inaccurate. Some of the colours developed on the strips I did have to guess at though as they did not compare to anything on the scales on the side of the tin, which is kind of shocking considering all the parameters are within range.
For the record the pool tested was In Ground, Tiled, holding 36,000 US Gallons, sanitation is Calcium Hypochlorite, source water is Soft = FC ~0.5; CC ~0.2; TA 40; CH 60; pH ~7.0
Stu
The test strips aren't that old, a customer had them when I started doing their pool, so instead of binning them they have just been cluttering up my testing case, but certainly gives good evidence that test strips are horrendously inaccurate. Some of the colours developed on the strips I did have to guess at though as they did not compare to anything on the scales on the side of the tin, which is kind of shocking considering all the parameters are within range.
For the record the pool tested was In Ground, Tiled, holding 36,000 US Gallons, sanitation is Calcium Hypochlorite, source water is Soft = FC ~0.5; CC ~0.2; TA 40; CH 60; pH ~7.0
Stu