11 Reasons Why Your Hot Tub Water is Cloudy (and How to Fix It)


Crystal clear water in a hot tub is not only aesthetically pleasing but also indicates that your water chemistry is healthy for soaking.  But what does it mean if your hot tub water is murky-looking? One thing for sure is that cloudy water is not a positive attribute in a hot tub. Today, let’s explore what might be happening to your hot tub water if it’s cloudy, and most importantly let’s look at how to fix those issues.

Cloudy water in hot tubs is typically caused by:

  • pH, Alkalinity and Calcium Hardness
  • Total Dissolved Solids
  • Pump Problems
  • Skin and Hair Care Products 
  • Not Enough Sanitizer 
  • Using Salt In A Hot Tub
  • Cloudy Input Water
  • Evaporation Issues
  • Too Much Organic Matter
  • High Usage
  • Spa Filter Cartridge Issues

If you’re experiencing cloudy water in your hot tub, there is no reason to worry. Today, we’ll cover everything you need to know about the reasons for cloudy water in hot tubs and how to fix it. After years of enjoying my own hot tub (and not necessarily enjoying the maintenance that has come with it), I have come to learn that many of the “issues” with hot tubs are actually pretty easy to resolve. Let’s take a closer look.

1. pH, Alkalinity and Calcium Hardness

If you have hard water you may also have issues with calcium, alkalinity, and pH issues levels in your hot tub. While you may not be able to change the fact that you have hard water, you certainly can fix your water chemistry issues in your hot tub.

How To Fix pH, Alkalinity, and Calcium Hardness Levels

Test for total alkalinity if you are having water hardness-related issues. If the alkalinity level is higher than 150 ppm, excess carbonate may be contributing to your cloudy water. A high TA level will also make it difficult to keep your pH level where it should be.

Apply a pH decreaser to lower the TA level until it reads around 100ppm. Keep the pH level in the range of 7.2-7.6.

2. Total Dissolved Solids

If it has been a long time since you drained your hot tub, then TDS, standing for total dissolved solids, may be contributing to cloudy water in your hot tub.

When water can’t absorb any more solids, it has reached its saturation point. If this happens then you most likely can expect cloudy water.

How To Fix Total Dissolved Solids Issues

When you get a TDS reading of 1500 or higher, it is time to totally drain your hot tub and refill it. This might seem like quite an overhaul, but it will be necessary once your hot tub reaches this point. Then, your next time in the hot tub should be quite refreshing, clean, and clear.

3. Pump Problems

Like any device, a pump can malfunction or stop working altogether. Or maybe you’re not allowing enough time each day for your pump to run. A pump running at too low of a speed can also have negative effects on water quality.

How To Get Your Pump Running Correctly

If your pump has totally stopped working, it’s time to read your manual or call the manufacturer to possibly help you troubleshoot pump issues. If your pump is still under warranty, you may be able to have it replaced with a new pump.

If the problem is that the pump is not running enough each day or at too low of a speed, that is the easiest fix. Make sure to run your hot tub pump for at least 2 hours each day. For a hot tub getting high usage, run it longer.

You may also want to take a look at your hot tub impeller. A clogged impeller may have debris that is preventing it from doing its job correctly. A clogged impeller will have a reduced flow volume. If the impeller is clogged remove the debris and try running it again.

4. Skin and Hair Care Products Releasing Into The Water

Not showering before using a hot tub can make the water become contaminated with products that hot tub users put on their skin and hair. Just take a look at the bathwater after you’ve used soap or shampoo. The water draining from a bath is seldom clear. Lotions also can wreak havoc on keeping your spa water clean.

How To Fix Cloudy Water Caused By Shampoos, Soap, and Lotion

This is a very easy fix and you probably already know the answer. Showering before getting in a hot tub will help to rinse off skin and hair products that can contaminate hot tub water. For this reason, at public hot tubs, you may have noticed signs saying to shower before entering the spa. Entering a hot tub clean just makes sense to keep the water clean.

5. Not Enough Sanitizer

Low sanitizer levels can make a hot tub cloudy rather quickly. Some people try to skimp in this area because they may not want certain chemicals in the water for health issues. They may be sensitive to chlorine or other additives. But by not adding enough sanitizer, not only can the hot tub become cloudy, but the water environment may become a health hazard for hot tub users.

Solutions For Low Sanitizer Levels

If you are concerned with skin sensitivities or allergies to certain chemicals used in a hot tub, try to find alternative additives. If a bromine or chlorine sensitivity is present, then try an Ozonator or maybe a mineral cartridge. It’s important to keep your pH level balanced at all times, whatever chemicals you choose to use.

If sensitivities are not an issue and you choose to go with commonly used sanitizers, then make sure to keep the levels in check. Bromine should have a level of 2-3 ppm or 3-5 ppm of chlorine. If sanitizers drop below 1.0 ppm, contaminants can start to take over. It’s much better to be proactive before that happens. 

Once contaminants start to take over they can quickly get out of hand, resulting in draining your hot tub and refilling it. Remember the old saying, “an ounce of prevention is worth a pound of cure.” This is certainly true when it comes to properly sanitizing your hot tub.

Another preventative measure is to shock the water after a lot of people have used your hot tub. Shocking a hot tub, simply put, means adding in extra chlorine or a chlorine alternative.

6. Using Salt In A Hot Tub

Adding salt to a hot tub or pool is a trend that is growing.  Some people enjoy the buoyancy that salt in the water provides. While it may be a popular choice, some people may become so confident that the salt is keeping their hot tub clean that they stop checking chlorine levels. Also, spa salt cells need to be routinely cleaned or cloudy water could result.

Solutions For Cloudy Water Due to Improper Chemistry Levels In Salt Water Hot Tubs

Make sure to maintain a proper chlorine level when using salt in your hot tub and also be diligent about cleaning the spa salt cells. Keep in mind that adding salt may temporarily cloud up your water. This is actually not a long-term problem. When the salt becomes fully dissolved that issue should go away on its own.

7. Cloudy Input Water

It can be very frustrating to fill your hot tub only to find that it’s already cloudy by the time it’s reached full water capacity. If you are having this issue, the problem is not with your hot tub system. So don’t panic! You shouldn’t have to empty your hot tub and then bring in water from an outside source. Let’s take a look at the solution below.

How To Fix Cloudy Fill Water

If your hot tub filtration system is working properly, your cloudy fill water issue should be able to correct itself. A spa clarifier can aid in clearing up cloudy fill water. You may even want to consider using a spa pre-filter to clean the water before it makes its way to your hot tub. A pre-filter can be attached to a garden hose and used while filling your hot tub.

8. Evaporation Issues

Over time evaporation may cause solids to become suspended in the water. If enough of these particles continue to build up, the water can become cloudy.

What To Do To Fix Evaporation Water Quality Issues

Sometimes it becomes necessary to drain and then refill your hot tub. When water evaporates again and again over time, each time it can leave mineral deposits in the water to become greater. When this happens, it’s best to drain your hot tub and refill it. In fact, it’s actually a good idea to drain your hot tub at a minimum of every six months. If you have hard water, the evaporation factor is more of a problem, so make sure to use a pre-filter when refilling your spa.

9. Too Much Organic Matter

If you are sure that your hot tub water has been properly sanitized and cloudy water still exists, you may have too much organic matter in your tub that the sanitizer is not fully addressing.

How To Reduce The Amount of Organic Matter

A clarifier may help to clear out cloudy water when all else fails. If you are sure your filtration system is working optimally and the water chemicals are in proper balance, then you may benefit from a clarifier. A clarifier is made to bind to organics. An ounce or two of a clarifying agent will often clear up cloudy water. Some people find that adding a small amount weekly also does the trick.

10. High Usage

The more your hot tub gets used, the more contaminants and debris will enter it. While of course this can be prevented by limiting the number and frequency of people using your hot tub, that’s probably not why you got a hot tub in the first place. Hot tubs are meant to be used and enjoyed.

Solutions For Keeping Highly Used Hot Tubs Clean

The higher the frequency that your hot tub gets used, the more the filter will need to run. Also, additional chemicals will most likely need to be added. You also may want to drain and add fresh water more frequently than a tub that is seldom used. For a highly used hot tub, try draining and refilling it a minimum of every 3 months.

11. Spa Filter Cartridge Issues

Your high hot tub usage might be the source of the problem, but this could also be more narrowly refined to the spa filter cartridge being used past its capacity. If you are noticing cloudy water in your hot tub and have not changed the spa filter cartridge within 15 uses or 1-2 years, then this could likely be the source of your problem. You may also find that the cartridge is simply positioned incorrectly and unable to perform appropriately.

How to Resolve Spa Filter Cartridge Issues

If you suspect that your spa filter cartridge is the source of the cloudy water in your hot tub, you can begin by thoroughly cleansing the spa filter cartridge before you attempt to use it again. Then, if this does not work, then it is likely time to replace the spa filter cartridge altogether.

If you are opting for the cleansing option, be sure to use a spa filter cartridge cleaner that can help to remove oil and dirt particles that may not be released by a simple rinse. Then, replace the spa filter cartridge correctly ensuring a snug fit on both ends of the filter. This will ensure that any water that passes through is actually going through the filter instead of around its insecure ends.

Finally, if you have been using your spa filter cartridge for what you know is too long (more than a year or two or 15 uses), then you will need to replace it altogether. It is suggested to keep track of the filter replacement date by writing it down in a secure and easily accessible location near your hot tub. This can help to ensure regular maintenance and reduce cloudy water from appearing in your hot tub.

Why is Your Hot Tub Water Foamy?

We’ve talked a lot about different problems with cloudy water in a hot tub. But what do you do when you notice foam on the top of the water? A lot of the same reasons that cause cloudy water also can cause foam to form at the top of the water. And the solutions are often the same.

Foamy water in hot tubs can be resolved with the following options: maintain the appropriate chemical balance, shower before entering, avoid using detergents (especially scented) on bathing suits/rinse before if used, use an antifoam product or a defoamer.

Let’s take a closer look.

How To Fix Foamy Hot Tub Water

To fix foamy water in a hot tub, try to identify the problem in the same way that we discussed fixing cloudy water. Always identify the cause before moving on to the solution. Simple preventative measures such as keeping chemistry numbers in check, adding proper amounts of chemicals, and showering before entering a hot tub should solve most of your foamy water issues. 

Also, consider not using detergents on bathing clothes. It usually is not necessary to use soap on bathing suits, but if you choose to do so, make sure to rinse out your suit thoroughly after washing and before entering your hot tub.

There are also anti-foam products on the market that are designed to eliminate foam in hot tubs. Most anti-foam products are designed to be a quick fix. Even though an antifoam product may get you quick results, also make sure to maintain your hot tub water as discussed in this article.

And lastly, on the topic of defoamers, overuse of these foam elimination products can actually cause cloudy water. So if you choose to use defoamers, make sure to use them sparingly.

Final Thoughts On Fixing Cloudy Water In Hot Tubs

Most hot tub owners will have cloudy water in their hot tubs at some point in time. This is nothing to be ashamed of or worried about. In fact, it’s totally normal. And remember, there is always a solution for fixing cloudy water. Most often the remedy is usually very easy once you identify what is causing the cloudy water.

After many years of experiencing the benefits of hot tubs and noticing this as a common issue for myself and other hot tub enthusiasts, I hope this article will help be a helpful guide for you as a hot tub owner in identifying what is causing cloudy water in your hot tub. And more importantly, I hope this information will be an aid for people to fix those issues so that they can get back to enjoying their at-home spas.

Jed Arnold

Jed spent every year from the ages of 15 - 22 as a Lifeguard (Red Cross) and ages of 17 - 22 as a Certified Pool Operator (CPO). Between working for over a dozen facilities and owning a pool, he carries over a decade of pool experience.

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