Side-by-Side Water Hardness Calculator

Compare Water Hardness Between Areas

Analyze real-time PPM, Clark degrees, limescale risk, and dishwasher salt settings between any two UK postcode sectors.

Water Quality Comparison Analysis

Executive Summary: Sector GU10 3 vs Sector SW1A 1

Comparing tap water mineral concentration between Sector GU10 3 (South East Water) and Sector SW1A 1 (Thames Water) reveals a water hardness difference of 10 PPM. Sector SW1A 1 has softer water at 275 PPM (Hard) compared to Sector GU10 3 at 285 PPM (Very Hard).

Limescale risk and boiler heating efficiency vary based on these mineral levels. Households in Sector GU10 3 experience higher heating element degradation and kettle scale accumulation due to elevated calcium carbonate density (285 PPM vs 275 PPM).

For home appliance setup, Bosch dishwasher water softener settings should be calibrated accordingly: Sector GU10 3 requires setting H05 whereas Sector SW1A 1 recommends setting H04.

NP

Sector SW1A 1 has 10 PPM LOWER water hardness than Sector GU10 3

Lower PPM indicates softer water, reduced limescale risk, and lower detergent usage.

Water Metric
Sector GU10 3Outcode: GU10
Sector SW1A 1Outcode: SW1A
Hardness (PPM)
285 PPM
275 PPM
Clark Degrees
19.9 °Clark
19.3 °Clark
Classification
Very Hard
Hard
Bosch Salt Setting
H05
H04
Water Supplier
South East Water
Thames Water
Postcodes Covered
170 postcodes
66 postcodes