Lamotte Waterlink Spin Lab Vs Taylor Drop Test

[matt_a_s]

Hello,

I brought my spa water for testing at two separate places with the following test results:

1st place (using taylor testing chemical drops)

free available chlorine: 5
total available chlorine: 7.5
calcium hardness: 50
cyanuric acid: 0
total alkalinity: 100
ph: 7.4

2nd place (using LaMotte WaterLink SPIN Lab)

free available chlorine: 3.32
total chlorine: 21.33
calcium hardness: 0
cyanuric acid: 15
total alkalinity: 76
ph: 7.3

With these results, I'm baffled as to why the test results are so drastically different in regards to the total available chlorine. The first place testing at 7.5 ppm compared to the 2nd place testing at 21.33 ppm????? Has anyone ever received similar test results for the total available that appear to be this drastic in comparison? One place is obviously totally off here and I'm not sure who's test to believe. Although, I've read a number of postings that the Taylor drop testing is more accurate. Therefore, any thoughts would be appreciated.

Regards,

Matt

 

[tim5055]

Welcome to TFP!

They are so vastly different because we find that most pool stores are horrendous at water testing. We don't recomend anyone go there to have water tested. We recomend you get your own quality/accurate test kit and use it for your own testing.

Also note, that yes, Taylor drop testing is better testing in our opinion, but only if done correctly. Most pool stores don't get it right, even when using Taylor tests.

 

[pooldv]

Welcome to TFP!

Thanks for showing yet again that pool store testing is unreliable and that we are correct to recommend that people test their own water at home with a good test kit like the TF-100 from TFTestkits.net.

 

[jeffchap]

This post should be required reading for every new user that comes on here with a set of pool store results.

 

[Brian VT]

I wish you (OP) could have also supplied your own results.
Please repeat after you get your own test kit.

I have screwed up with a test kit. I might anticipate how many drops it will take before changing the color so I "cheat" and add more than one drop at a time. Then I blow right by the indicator and have to start over.
The guy at the store might do the same but not bother to start over. He just gives you a number.

 

[Eauclaire]

It would be interesting to obtain 'same operator' statistics on the Lamotte Spinlab. The cell filling phase requires a repetitive light touch to prevent over or underfilling. The printed computerized suggested 'corrective measures' are usually overkill; trying to correct every little deviation on every single measured variable. Some AI is clearly missing here.

 

[cjbyrd]

My local ACE uses the WaterLink Spin computer test. Sometimes it's close to my taylor kit results and sometimes it's way off.

 

[dmattle]

2 pool stores ran the Waterlink Spin test and came back with the same results for CH (200).My Taylor reagents came up with 350 (ran around 4 or 5 times with new reagents). 1 pool store ran the Taylor reagents and came up with 420 (added an extra 5 drops once water turned blue). Any idea why Waterlink test so far off? If i use 200 CH CSI shows 'Potential to become corrosive to plaster'
Results using Taylor reagents.
FC=7.6
CC=0
TA=60
CH=350
CYA=40
Borates=50
Water temp=85

 

[tim5055]

2 pool stores ran the Waterlink Spin test and came back with the same results for CH (200).My Taylor reagents came up with 350 (ran around 4 or 5 times with new reagents). 1 pool store ran the Taylor reagents and came up with 420 (added an extra 5 drops once water turned blue). Any idea why Waterlink test so far off? If i use 200 CH CSI shows 'Potential to become corrosive to plaster'
Results using Taylor reagents.
FC=7.6
CC=0
TA=60
CH=350
CYA=40
Borates=50
Water temp=85

No real idea why, just stick with your numbers.

 

[dmattle]

Thanks.