General • Inspections

TS: Water Hardness Test

This procedure explains how to perform a water hardness test using the Hach 5B kit. It includes preparation, reagent mixing, titration, and recording hardness levels to ensure water quality is within acceptable limits.

Tosca Newnan GA

08/27/2025

TS: Water Hardness Test

If needed, review the instructional video and/or additional info

See attached pictures as well for more details; Picture 1 shows all components of the kit. From left to right: Test Tube, Mixing Bottle, Reagent Powder & Dipper, Titrant Solution with attached Dropper Picture 2 shows the instructions printed on the box

Hach 5B Water Hardness Test Instructions

Rinse and empty the test tube and mixing bottle with soft water x3 times

Fill the test tube all the way with soft water

Place the mixing bottle upside down on top of the test tube and flip to pour the contents of the test tube into the mixing bottle

Scoop one level dipper amount of reagent powder, dump into the mixing bottle, and gently swirl

Take a picture of the mixing bottle with only the soft water and reagent powder added

Add or drag pictures

Is the solution in the mixing bottle pure blue?

Mark as "No" if the solution is purple, pink, or red

Yes
No
N / A

if the answer is "oneOf [Yes]"

Record a value of 0

Meter name

Unit

Rinse & Empty the test tube & mixing bottle and return all supplies back into the box

if the answer is "oneOf [No,N/A]"

Add a drop of the Titrant solution one at a time into the mixing bottle, while swirling until it is blue.

Record the number of drops needed to turn the solution blue

This number is the grains of hardness, for example one drop = 1 grain of hardness per gallon of water. Take a picture of the bottle after adding the Titrant solution

Meter name

Unit

Rinse & Empty the test tube & mixing bottle and return all supplies back into the box

Source: Tosca Newnan GA (Community Member)