FROG SooTHe^® Total Hardness Increaser

Total Hardness increaser for hot tubs or swim spas

Calcium chloride-based water treatment designed to safely raise calcium hardness in hot tubs or swim spas. This protects equipment from corrosion, prevents surface pitting and ensures a comfortable, crystal-clear soak.

Starting at $13.95

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Benefits

Granular hot tub or swim spa chemical
FROG TruDose Cap^™ with built-in measurements
Compatible with all FROG sanitizing systems

Directions for Use

Test the water weekly with a test kit or test strips to make sure your Total Hardness level is in the correct range of 150 to 250 ppm.
Measure the dose: Look at the chart on the FROG SooTHe bottle to find the right amount for your gallon size. Use the built-in FROG TruDose Cap^™ to measure an accurate amount.
Add to the water: Turn your jets on. Pour the measured product directly into the water. Make sure nobody is using the hot tub or swim spa.
Circulate: Keep the jets running for 30 minutes with the cover off.
Retest: Wait 2 hours, then test the water again. Repeat these steps if the hardness is still below 150 ppm.

Manuals & Documents

FROG SooTHe Safety Data Sheets (English)

Front of a blue and white FROG SooTHe Total Hardness Increaser container, on a white background.

Back of a FROG SooTHe Total Hardness Increaser container showing the directions, on a white background.

Clear measuring cup included with FROG SooTHe Total Hardness Increaser, marked from 1/8 to 1 cup, on a white background.

Hands pouring white granular water treatment from a bottle into a clear measuring cup over a hot tub.

Hand pouring granular water treatment from a measuring cup into a bubbling hot tub.

Whenever your Total Hardness is lower than 150 ppm. The ideal Total Hardness range for hot tubs and swim spas is 150 to 250 ppm. See the handy dosage chart on the bottle for hot tub or swim spa gallon sizes.

SooTHe is a fun way of saying this product will make your water more soothing by providing the correct level of Total Hardness.

This Total Hardness Increaser comes in a bottle with the FROG TruDose Cap and an easy to read dosage chart which makes it much easier to measure out the right amount of chemical for each individual hot tub or swim spa.

Yes – this is compatible with all other sanitizing products like chlorine, bromine, ozone, UV and salt generators.

1 bottle of FROG SooTHe Total Hardness Increaser

Also known as calcium hardness, Total Hardness refers to the amount of calcium and other minerals in the water that make it feel “hard” or “soft”. Hot tub and swim spa water should maintain a Total Hardness level between 150 – 250 ppm. This should be tested when you first fill your hot tub pr swim spa.

When Total Hardness is below 150 ppm, the water can be corrosive; if it’s above 250 ppm, the water may cause scaling. If you have the option of filling the hot tub or swim spa with softer water, you can always add hardness. If your water is hard from the faucet, then it requires more work to get it balanced. Without balanced Total Hardness, it will be very difficult to maintain proper balance and sanitizer levels and damage to the spa is almost certain.

Most often it is due to the water that comes out of your tap to fill the hot tub. Every municipality is different, and many people have well water. Every time you add water to your hot tub or swim spa to evaporation, you are changing the Total Hardness.

The best option is to find a soft water source to fill your hot tub or swim spa. Short of that, it’s great to check with your local dealer who understands what it takes to remove Hardness from spas in your region. If you don’t get the Hardness below 250 ppm, you will experience less effective sanitizing and damage to surfaces or equipment.

Low Total Hardness will search for any type of calcium and pull it from the spa surfaces which results in pitting or etching. It also dries out skin and makes soaking an uncomfortable experience. However, there is an easy fix for this and that is to add a hardness increaser like FROG SooTHe.