Saturation Index

[chem geek]

would you please check the accuracy of this calculator when you get some spare time?

http://www.aquachek.com/calculators....lculator&CID=4

Thanks!!
Donnie

I get somewhat different results, especially at higher temperatures such as those found in a spa (about 0.2 units different). The differences are small at normal temperatures -- within 0.1 units. Again, I wouldn't worry about such small differences. If you want an accurate calculator that pretty much matches the Taylor watergram (except for the highest temperatures well above spa temperatures where it is off by 0.1), then go to the end of the first post in this thread and download my spreadsheet in the PoolEquations.zip file. It calculates both the traditional LSI as well as the more accurate one that matches the Taylor watergram.

Richard

[DONNIE]

So I don't need to include TDS in the saturation index or do I use my 3600 ppm salt?

[chem geek]

So I don't need to include TDS in the saturation index or do I use my 3600 ppm salt?

You should include it in the index, using say 3800 ppm (200 ppm more than the salt measurement), but don't bother measuring TDS explicitly.