how to increase water hardness in hot tub

3 min read 22-01-2025

how to increase water hardness in hot tub

Maintaining the proper water chemistry in your hot tub is crucial for a comfortable and enjoyable soak. One important aspect is water hardness, measured in parts per million (ppm) of calcium. Too little hardness can lead to corrosion of your hot tub's equipment and surfaces. This guide explains how to increase water hardness in your hot tub safely and effectively.

Understanding Water Hardness in Hot Tubs

Water hardness refers to the mineral content, primarily calcium and magnesium, dissolved in the water. Ideally, your hot tub water should have a hardness level between 150-250 ppm. Levels below this are considered soft, while levels above are considered hard. Soft water is corrosive and can damage your hot tub's components, including the heater, plumbing, and shell.

Why is proper water hardness important?

Corrosion Prevention: Sufficient hardness acts as a buffer, preventing corrosion of metal parts.
Scale Prevention: While too much hardness can lead to scale buildup, a moderate level helps prevent scale formation.
Water Clarity: Proper hardness contributes to clearer, more sparkling water.

Testing Your Hot Tub's Water Hardness

Before you add anything to your hot tub, you need to know your current water hardness. Use a reliable test kit specifically designed for hot tubs. These kits usually provide a simple color comparison or digital reading to determine your water's hardness level.

What to do with the results:

Hardness below 150 ppm: You need to increase the hardness.
Hardness between 150-250 ppm: Your hardness is ideal.
Hardness above 250 ppm: You need to decrease the hardness (this is less common, and involves using a water softener or other specialized methods).

How to Increase Water Hardness

There are several ways to increase water hardness in your hot tub. The most common and easiest method is using calcium chloride.

Using Calcium Chloride

Calcium chloride is readily available at most pool and spa supply stores. It's important to follow the instructions on the product packaging carefully, as the amount needed will vary depending on the size of your hot tub and the desired increase in hardness.

Step-by-Step Guide:

Test the water: As mentioned before, always test your water first.
Calculate the needed amount: Use the product instructions and your test results to determine the correct amount of calcium chloride to add.
Dissolve the calcium chloride: Before adding it to the hot tub, dissolve the calcium chloride in a bucket of water. This prevents it from clumping and ensures even distribution.
Add slowly: Slowly pour the dissolved calcium chloride into the hot tub, while the jets are running. This helps distribute the calcium chloride evenly throughout the water.
Retest the water: After adding the calcium chloride, wait 24 hours, then retest the water to ensure you have reached the desired hardness level. You may need to add more calcium chloride in small increments until you reach the ideal range.

Other Methods (Less Common)

While calcium chloride is the most practical method, other options exist, but are less frequently used:

Calcium Hardness Increaser Tablets: These are convenient, but may not be as cost-effective as calcium chloride.
Using a Water Softener (Reverse): While water softeners typically reduce hardness, some advanced models can be adjusted to increase hardness. This is generally not recommended for hot tubs due to the potential complexity.

Maintaining Proper Water Hardness

Once you've adjusted your water hardness to the ideal level, regular testing and maintenance are key. Test your water regularly (at least weekly) and adjust the hardness as needed. Remember, consistently maintaining the proper water chemistry will prolong the life of your hot tub and ensure a more enjoyable bathing experience.

Important Note: Always follow the instructions on the product packaging for the specific chemicals you're using. If you are unsure about any aspect of water chemistry maintenance, consult a professional hot tub service technician.

FAQs:

Q: Can I use tap water to fill my hot tub? A: While possible, your tap water’s hardness may vary significantly. It is best to test before filling to know what adjustments are necessary.

Q: What happens if my water is too hard? A: Excessive hardness can lead to scale buildup on your hot tub components. This may require more intensive cleaning and may damage the equipment over time.

Q: How often should I test my hot tub water? A: At least once a week, and more frequently if you use the tub regularly.

By understanding how to test and adjust your hot tub’s water hardness, you'll contribute greatly to its longevity and your enjoyment of relaxing in your own private spa. Remember always to prioritize safety and follow manufacturer instructions.