# How is Langelier Saturation calculated?

## How is Langelier Saturation calculated?

LSI Formula: A = (Log10[TDS] – 1)/10 = 0.15. B = -13.12 x Log10(oC + 273) + 34.55 = 2.09 at 25°C and 1.09 at 82°C.

## How do you calculate the saturation index of water?

The formula to calculate LSI is: (pH) + (Temperature ºF) + (Calcium Hardness) + [(Total Alkalinity) – (CYA correction factor @ current pH)] – (TDS factor) = LSI.

How do you calculate LSI in a pool?

Use the formula pH + Temperature Index + Calcium Index + Alkalinity Index – TDS index. We’ll get: 7.3 + 0.7 + 1.9 + 2.0 – 12.1 = -0.2 which falls within acceptable levels when we’re talking about home pool LSI index.

### What is Langelier Saturation Index?

The Langelier Saturation Index (LI), a measure of a solution’s ability to dissolve or deposit calcium carbonate, is often used as an indicator of the corrosivity of water. The Langelier Index is defined as the difference between actual pH (measured) and calculated pHs.

### How do I find my Langelier index?

The LSI index is calculated at two temperatures: 25oC (room temperature) and 82oC (cage wash cycle)….pHs = (9.3 + A + B) – (C + D) where:

1. A = (Log10[TDS] – 1)/10 = 0.15.
2. B = -13.12 x Log10(oC + 273) + 34.55 = 2.09 at 25°C and 1.09 at 82°C.
3. C = Log10[Ca2+ as CaCO3] – 0.4 = 1.78.
4. D = Log10[alkalinity as CaCO3] = 1.53.

What does Langelier index measure?

The Langelier Index is an approximate measure of the saturation degree of calcium carbonate (CaCO3) in water. It is calculated using the Hydrogen Ion (pH) , Alkalinity (CaCO3), Calcium concentration, Total Dissolved Solids, and water temperature of a tap water sample.

## What should LSI be?

In short, the LSI tells us how saturated our water is with calcium carbonate (CaCO3). Perfect saturation is 0.00 LSI, and the acceptable range is between -0.30 to +0.30 LSI. If the LSI is -0.31 or below, water is aggressive because it is under-saturated with calcium carbonate.

## What is the formula for saturation index?

The formula is “SI = pH + TF + CF + AF – 12.1.” To calculate the Saturation Index, test the water for pH, temperature, calcium hardness, and total alkalinity.

How can I reduce my LSI?

Add muriatic acid to decrease the pH and LSI value.

### What is Langelier Index & Ryznar Stability Index?

The Ryznar index is based loosely off of the Langelier saturation index that was created in the 1930s. The Ryznar index is logarithmic, similar to other indices that are used to calculate calcium carbonate formation. Generally, any value above 6 indicates that the water is likely to form a calcium carbonate scale.

### What is a Langelier test?

The Langelier Saturation Index (LSI) is a cornerstone of the Orenda program. The LSI is the unbiased measurement of water balance, as defined by calcium carbonate saturation. It determines if our water is aggressive/corrosive (low LSI), balanced, or scale-forming (high LSI).

What is LSI balance?

Langelier Saturation Index (LSI) is a method of measuring how “balanced” the water in a pool is. This determines if the pool water is going to have any effect on equipment, and what that effect might be.