What is The Saturation Index and How Do I Calculate It?

The Saturation Index or SI Index is a calculated number for determining if your pool’s water is corrosive or scaling. If your water is corrosive (less than -0.3), the pool’s water will dissolve calcium in pool linings and protective coatings. If your water is scaling (greater than +0.3), calcium will be deposited on pipelines, filters, valves, and pump. The balanced range is between -0.3 and +0.3 which has no effect on pool mechanical equipment.

Methods for calculating the SI-Index

1. SI Equation and Table
SI = pH + Temperature Factor (TF) + Calcium Factor (CF) + Alkalinity Factor (AF) - 12.1

Saturation Index Chart

2. Online Calculator
There are several online calculators to help figure Saturation Index based on multiple input variables. There are multiple iOS and Android apps that do the same thing on your mobile device. Click Here for an example of just one.

3. Taylor Watergram
To calculate the SI Index with the Taylor Watergram move the concentric circles to their appropriate values to find your SI Index.

Taylor Watergram

4. DigiQuatics

Simply customize your Locations and Pools using the admin dashboard settings. Once setup, easily select the Location and Pool, fill out Temperature, Alkalinity, and Calcium Hardness in the New Chemical Record form.

If required fields are submitted with data, the Saturation Index will automatically be calculated and color coded. All the data is stored in our backed up online database, accessible anywhere, anytime on your favorite mobile device!

Chemical Records Index DigiQuatics
You can even get analytics on your pool for any custom date range to better optimize your pool chemistry levels!
Chemical Analytics with SI

To learn more or to start a 30 day free trial at your facility, visit www.digiquatics.com.

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