foamy hot tub water

Why do hot tubs go green? Spa water fixes

The color of water is not likely to be a popular conversation topic. After all, does it even have a color? But if you have ever walked outside to enjoy a relaxing soak in your hot tub and noticed the water is green, it might be the only thing you can talk about.

Why do hot tubs go green? There are two likely reasons your spa water is resembling the lawn below instead of the sky above. Green hot tub water can be caused by minerals, such as iron and copper, or an algae bloom.

While you want to relax in your hot tub instead of working on your water, a little effort can go a long way to make your water clean, clear, and inviting.

By the way, water does have a color — even if it looks clear in your drinking glass. Pure water should have a slight blue or turquoise hue to it. Your hot tub water, when it’s properly sanitized and balanced, should also have an icy blue color.

owning a hot tub
Master Spas makes buying and owning a hot tub just as relaxing as using one.

Why do hot tubs go green?

Is your once aqua-hued spa water now taking on a green tint? An easy test to determine the culprit is to run your hand along the wall of the spa. Squeaky clean? It’s a mineral problem. A bit slimy? You might have an issue with algae.

Minerals such as iron, copper, and manganese can affect the color of your hot tub water. Your source water, whether it comes from the city or well, could contain heavy metals. When you add oxidizer to the water, it activates the minerals and turns the water green.

Hot tub water can also turn green because of algae. Warm water that has not been chlorinated is the perfect place for algae to grow. When you don’t add enough sanitizer, such as chlorine, algae can make itself at home. 

Spa owners should expect to balance chemicals several times a week, adding chlorine and a shock treatment as necessary. These hot tub chemicals help keep your water clean and clear so it’s safe for soaking. 

But it might be more than just adding a capful of chlorine when you get out of the spa. Leaving the cover off of your spa, especially in the summer, can deplete your chlorine. In addition, algae can be introduced to your hot tub water via swimsuits. If you or a loved one has been swimming in the lake, be sure to thoroughly rinse the swimwear before getting in the hot tub.  Or better yet, keep a separate swimsuit just for hot tub use.

chlorine bromine hot tub
The right sanitizer will keep your hot tub water clean and clear. Master Spas owners should use chlorine because it works best with the EcoPur Charge filtration system.

Clean your hot tub

The first step in reviving your spa water is to get out a test strip. If you suspect that your water is green because of minerals, you want to make sure all of your chemicals are balanced.

Your hot tub test strips will measure the total hardness, total chlorine, free chlorine, alkalinity, and pH of your water. Once you have tested the water, you’ll know what adjustments to get the levels in the correct range. Remember: Balance alkalinity first and then pH before tackling chlorine.

A sequestering agent can also help remove any heavy metals from the water. Be sure to follow the directions on the bottle and let it cycle through. It can be helpful to rinse and clean the filters after the sequestering agent has done its job.

If you suspect algae turned your hot tub water green, the best course of action is to drain your spa. Draining your hot tub will allow you to thoroughly clean the shell, wash the spa pillows, and deep clean the filters. Your goal is to remove any traces of algae before refilling the hot tub.

Another hot tub accessory to clean is the cover. Residual algae can be on the material because of condensation. Use a cleaner designed for marine-grade vinyl.

Once your hot tub is clean, you can put in the filters, add water, and balance the chemicals.

best way to clean hot tub filters
Your hot tub filters play a key role in keeping your hot tub water clean. It’s important, though, to properly maintain your filters so they can best do their job.

Prevent green hot tub water

Water care is key to keeping your hot tub safe for soaking. Master Spas recommends testing your water on a regular basis and adding chlorine several times a week. When your free chlorine levels are too low, you might experience problems like green hot tub water. Master Spas owners should use chlorine to sanitize the water, as it works best with the mineral filtration system.

In addition, it’s important to pay attention to your filter cycles. Filters are vital to keeping your water clean. Use the control panel to view and change your filter cycles. Increasing the length of cycle can help filter out elements that you don’t want, such as dirt, bacteria, and algae.

But water care does not have to be time consuming. Master Spas hot tubs are designed to be easy to use and easy to maintain. The EcoPur mineral filtration system uses natural elements, such as copper and zinc, to keep the water clean. Requiring fewer chemicals compared to other brands, you can spend less time caring for the water and more time soaking in it.

how to buy a hot tub
Make the most of your backyard with a Master Spas hot tub. Easy to own and easy to enjoy, you can relax and unwind at home.

How to buy a hot tub

Look forward to spending more time in your own backyard oasis. A Master Spas hot tub can be enjoyed safely by the entire family. You can click here to learn more about the benefits of hydrotherapy. Or, contact your local Master Spas retailer to learn more about spa ownership. Wondering how much a Master Spas hot tub costs? You can request a quote here.