new SWG, different results using different tests

[topherchris]

I had a Hayward Aquarite with t-15 cell installed yesterday. Pool is 15000 gal so per pool math we needed ~400 lbs of NaCL. We added 320 lbs yesterday to avoid overshooting. Per pool math, that should get us to ~2600. Aquarite reads 2600 with lights on "check cell" and "check salt" lights flashing. I used a salt testing strip, picture attached, and got 6.6=3040. I used taylor k-1766 salt test and got 18 drops= 3600.

1.) Did I read the salt strip correctly? I read it from the tip of the yellow line at 6.6, but the base of the peak is at ~6 which would put it about 2400. 2400 seems more would I would expect based on the amount of salt added.
2.) Why is my taylor test reading so high? I used the speedstir and stopped the test as soon as it turns from yellow to red which was 18 drops. I was thinking that the taylor test would be more accurate, but it's way off. It's a new kit.
3.) How accurate is the cell at determining the salt content? How do most people do their salt testing?

Thanks

 

[mknauss]

Use the Taylor K1766 result. It is by far the most accurate of the three.

Salt cell is the least accurate of the three. They do not continuously check salinity. So see if the salinity rises and stabilizes over time.

 

[topherchris]

Thanks, mknauss. Is there something I'm missing with the k1766 test? I don't think that I'm overtitrating. Anyone else have trouble getting an accurate value?

 

[Msch99]

If you have had the pool awhile, some salts will have built up from normal chemical use, some of which have salts in them.

 

[BadDogPSD]

If you have had the pool awhile, some salts will have built up from normal chemical use, some of which have salts in them.

I bought the K-1766 salt test in preparation for doing the conversion. Our pool measured 1200ppm of salt with no salt added other than what's in the chlorine.

 

[topherchris]

I measured before adding salt and got 1000, but now I'm questioning if that was accurate

 

[mknauss]

I measured before adding salt and got 1000, but now I'm questioning if that was accurate

With the K1766? The 2600 ppm of salt you added with the 1000 ppm before -- equals 3600 ppm.

 

[lager1829]

Always believe Marty. And the Taylor tests

 

[topherchris]

Yeah, the results I'm getting with the k1766 are consistent but are not corresponding with other test methods. I added another bag of salt and the lights on the swg went off so I guess its happy.

 

[mknauss]

Good -- but be ware if the salinity the SWCG senses goes up over the next day or two. Higher salinity can mess up the electronics of the Hayward controllers. Just monitor.

 

[topherchris]

Will do, thanks

 

[topherchris]

Also, how would u read the salt test result in the picture I posted? 6.0? 6.8?

 

[mknauss]

Also, how would u read the salt test result in the picture I posted? 6.0? 6.8?

No idea. I have never used any form of test strip.

 

[Hootz]

It may take awhile for the salt reading of your swg controller to get closer to the reading of the Taylor test kit, but it may never agree. The salt levels reported by most swg are not as accurate as the Taylor test kit. I find with my pool when adding salt it may take up to 48 hours for the salt level readings to stabilize regardless of the test type. It would seem that a new swg would be accurate as far as salt level readings but most are not. Depend on the k1766 results.

 

[Msch99]

Hopefully your SWG won’t decide your salt too high in the next couple of days. The only way to lower salt or CYA is to drain and refill.

 

[Saturn94]

I had a Hayward Aquarite with t-15 cell installed yesterday. Pool is 15000 gal so per pool math we needed ~400 lbs of NaCL. We added 320 lbs yesterday to avoid overshooting. Per pool math, that should get us to ~2600. Aquarite reads 2600 with lights on "check cell" and "check salt" lights flashing. I used a salt testing strip, picture attached, and got 6.6=3040. I used taylor k-1766 salt test and got 18 drops= 3600.

1.) Did I read the salt strip correctly? I read it from the tip of the yellow line at 6.6, but the base of the peak is at ~6 which would put it about 2400. 2400 seems more would I would expect based on the amount of salt added.
2.) Why is my taylor test reading so high? I used the speedstir and stopped the test as soon as it turns from yellow to red which was 18 drops. I was thinking that the taylor test would be more accurate, but it's way off. It's a new kit.
3.) How accurate is the cell at determining the salt content? How do most people do their salt testing?

Thanks

The yellow extends past 6.6, so I would read that as 6.8. You read the tip of the yellow.