Salt Water Generators Raise Ph Level?

[waterbear]

Thanks.

what do you think of those Exact electronic tester?

Not a whole lot.

[Gavin]

Thanks.

what do you think of those Exact electronic tester?

Not a whole lot.

really? I heard they were so accurate. but I wondered why no one here or at TFP recommended anything other than Taylor K2006 or the TF kits.

[waterbear]

EEE

Thanks.

what do you think of those Exact electronic tester?

Not a whole lot.

really? I heard they were so accurate. but I wondered why no one here or at TFP recommended anything other than Taylor K2006 or the TF kits.

Exactly

[chem geek]

Gavin, remember not to confuse "precision" with "accuracy". The tester you refer to claims a "precision" of .01 ppm, but that just means they have a measurement system and readout with two decimal digits. It does not mean that the value is "accurate" to within that tolerance. It may be significantly biased or have a lot of variation over time. Because the chlorine test uses the DPD method, it will bleach out at higher chlorine levels so will start to have less accurate readings above 5 ppm and will probably be completely bleached out above 10 ppm. Other tests may have similar kinds of limitations.

Of course, if you do buy this device, you can compare it to the Taylor K-2006 and tell us if it is truly accurate. At least with the Taylor kits, they guarantee specific accuracy, usually within one drop for most tests, which means FC/CC to within +/- 0.2 ppm for a 25 ml sample size and +/- 10 ppm for most other drop tests. The dropper tips for the Taylor tests are 24 drops per ml +/- 1 drop so some inaccuracy comes from that while some comes from reagent concentrations.

[Gavin]

Gavin, remember not to confuse "precision" with "accuracy". The tester you refer to claims a "precision" of .01 ppm, but that just means they have a measurement system and readout with two decimal digits. It does not mean that the value is "accurate" to within that tolerance. It may be significantly biased or have a lot of variation over time. Because the chlorine test uses the DPD method, it will bleach out at higher chlorine levels so will start to have less accurate readings above 5 ppm and will probably be completely bleached out above 10 ppm. Other tests may have similar kinds of limitations.

Of course, if you do buy this device, you can compare it to the Taylor K-2006 and tell us if it is truly accurate. At least with the Taylor kits, they guarantee specific accuracy, usually within one drop for most tests, which means FC/CC to within +/- 0.2 ppm for a 25 ml sample size and +/- 10 ppm for most other drop tests. The dropper tips for the Taylor tests are 24 drops per ml +/- 1 drop so some inaccuracy comes from that while some comes from reagent concentrations.

Thanks for clearing that up. that makes sense. I think I'll stick to my Taylor k2006 for now and then upgrade to the TF-100 XL kit.

The CYA test in the Taylor is harder to read. I don't when the dot just disappears. It seems to take some time to fade away. Hmmm...bigger tube might help like I think the TF's carry. also like the larger reagents in the TF's. If I get an iTouch and load the pool calculator on it and get a TF-100 XL test kit I will be well sorted.

[Mark]

IMHO, I think the salt tests are rarely required. Even if it is not all that accurate, the reading from the SWG itself is probably the most important salt level. If the unit reports salt level is too high or low and shuts off, it really doesn't matter what the "true" level is only that you will need to add or remove salt to make the unit happy. The only time where true salt level can come in handy is when the cell is nearing the end of life and will tend to read the salt level on the low side. The further away from the true level, the closer to the time the cell will need to be replaced. Other than that, I rely upon the unit to tell me when to add salt.

[Gavin]

IMHO, I think the salt tests are rarely required. Even if it is not all that accurate, the reading from the SWG itself is probably the most important salt level. If the unit reports salt level is too high or low and shuts off, it really doesn't matter what the "true" level is only that you will need to add or remove salt to make the unit happy. The only time where true salt level can come in handy is when the cell is nearing the end of life and will tend to read the salt level on the low side. The further away from the true level, the closer to the time the cell will need to be replaced. Other than that, I rely upon the unit to tell me when to add salt.

Thanks yes that makes sense. I had a reading of 2,600ppm but when I checked with the Taylor salt test it read 2,800ppm. I added 25lbs of salt and now the SWG is reading 2,800ppm and generating chlorine good now. had to turn down to 60%.

[2n3055]

Use a 20 mL sample with the Taylor salt test, each drop of titrant is then equivalent to 100 ppm NaCl, the test is that much easier to perform because there is less of a chance to overshoot the endpoint.

[chem geek]

Yes, I use a 25 ml sample size where each drop is 80 ppm salt. The Taylor K-1766 has a 20.5 ml mark, not 20 ml, but that's close enough. I use the 25 ml mark and just multiply the number of drops by 80.

[polyvue]

Use a 20 mL sample with the Taylor salt test, each drop of titrant is then equivalent to 100 ppm NaCl, the test is that much easier to perform because there is less of a chance to overshoot the endpoint.

I have no issues with overshooting the end point titrating 10 mL or 25 mL samples--it's unmistakable and dramatic. When approaching the end point, I'm pretty focused, slowing down to a drop at a time, swirling for about 1 second between drops. Haven't missed it yet.

My problem occurs earlier in the titration when I'm working quickly to reach 10 or 30 drops. Too often, my right hand fails to consult with the left hand before squeezing out the drops. If the left hand that is swirling varies the arc, creating a slightly wider circle, or moves off-target, the drops overshoot the sample tube, splattering silver nitrate solution onto my hand... an instant free-form tattoo.

Probably comes from being so cocky about the end point!

[waterbear]

Have you considered investing in a magnetic stirrer? They are wonderful for the salt and CH tests! (AND worth every cent, IMNO!)

[chem geek]

There used to be a magnetic stirrer from Apollo, but it is no longer being manufactured. However, Taylor now makes the K-9265 which you can also get from tftestkits.com.

[polyvue]

Have you considered investing in a magnetic stirrer? They are wonderful for the salt and CH tests! (AND worth every cent, IMNO!)

Yup. Definitely on my shopping list. Was sorry to see the Apollo go away before I had a chance to purchase.

There used to be a magnetic stirrer from Apollo, but it is no longer being manufactured. However, Taylor now makes the K-9265 which you can also get from tftestkits.com.

$34.50 is a fair price. Don't suppose I'll get in trouble here by mentioning a fairer one: $26.25 Lincoln Aquatics

http://www.lincolnaq...ductID=25%2D002