Difference between Poolmath web and Poolmath app

[dws3]

I have an issue with the results of the Poolmath Android app versus the web version. I am seeing a different result in the CSI, with the app providing a more negative result of 0.1, give or take. This can make it look like my water is unbalanced when it's not, or balanced when it's not, and it has me wondering which source is correct. Since I paid for the premium version of the app, I sent an inquiry to the support contact about two weeks ago, but have never received a response. I thought I would ask the forum and see if anyone has noticed this, or has an opinion on which source is correct, and why they don't provide the same result. For example, today's water test is shown below:
FC - 2.4
CC - 0.0
pH - 7.8
TA - 110
CH - 240
CYA - 30
Temp - 59 F
CSI App - 0.03
CSI Web - 0.12

In this case, the result doesn't really matter, but if the two sources are not using the same algorithms, it would be nice to know which one is more accurate.

 

[Texas Splash]

dw, I believe that is because the APP automatically assumes a baseline salt content of 1000 since even non-SWG pools see an increase in salt over time. That 1000 ppm of salt seems to make the difference. @Leebo can you confirm please?

 

[Rancho Cost-a-Lotta]

I just tested out the two apps yesterday and compared results. In my case, the results are off by only 0.01 (-0.25 and -0.26).

 

[Leebo]

@Texas Splash is correct, make sure your salt level is the same. I highly suspect your entry on the webpage is zero. Also make sure you’re using the newest version of the webpage by hitting F5 to refresh things.

As for the difference @Rancho Cost-a-Lotta pointed out, that’s just a difference in rounding

 

[RMcGirr83]

CSI with the app and inputting nothing states .03?

 

[Texas Splash]

CSI with the app and inputting nothing states .03?

Because it has a default salt level of 1,000 already loaded. The old Poolmath web page does not.

 

[dws3]

Hmmm...never even considered entering salt. I didn't turn on the "Track Salt" option, since I don't test for salt. Guess I'll turn that on, load 1000, and start loading 1000 into the web app, as well, as a check.

 

[Leebo]

All forms of chlorine and Muriatic Acid will add salt. To help give the user a more accurate number we’ve updated things to use 1,000 as you’ve gotta have some salt in your water. As mentioned, hit F5 on your computer and you’ll see the web version update as well.

 

[dws3]

I purchased a salt test kit and used it today. My current reading is only 400 ppm, but that's probably because my pool builder came out a couple of weeks ago and drained everything except the deep end of the pool in order to make a repair to their recent Pebble-Tec remodel in the shallow end, so I have not added much bleach or MA in the interim. Thanks to all for the learning experience.

 

[RMcGirr83]

1,000 is a hunch and probably a pretty bad one at that.