Help! My Hot Tub Water is Murky!


If you own a hot tub, you may encounter all kinds of problems that need to be solved. Murky water is one of the most popular. Under this generic term, water that is cloudy, misty or anything that is not crystal clear is represented. The milky appearance of water is caused by particles floating in the water, which give it its murky appearance. These particles are too small to be reached and too small to get caught in the filter, so they run straight ahead and stay in the water.

These particles can consist of different substances: organic matter, insoluble matter, cosmetic products such as moisturizers, lotions and dead algae. In some cases, the bather releases the particles. If you remember a hot tub, unlike a swimming pool, has a very limited amount of water for each person. Ultimately, there is a higher concentration of particles in the water, which leads to cloudiness.

Now you have a mental picture that is adequately inspiring, it’s time to figure out the potential reasons and solutions for your murky hot tub water.

Hot Tub Water Filtration

Good filtration is a key factor in producing clean, sparkling water in a hot tub. Some hot tubs are equipped with cartridge filters. It is important to know what the filter manufacturer recommends for cleaning. It is recommended that the hot tub filters be rinsed once a week and soaked in a filter cleaner once a month.

Most manufacturers offer a wide range of filter cleaners including Filter Heal, Filter Nice and Revive Filter. Without proper filtration you’ll find yourself in a dark and filthy bath in no time. But if you handle it correctly, you don’t have to fear that poor filtration is the source of your murky water.

Hot Tub Water Circulation

It also plays an important role in obtaining clean water. When properly circulated, the water can easily flow through the filter for filtration. Circulation also helps to disperse chemicals added to the water. The water is drained from the hot tubs as the pump draws the water through the skimmer and filter before it enters the jets.

The best circulation system for your hot tub provides water that circulates continuously. A beachcomber hot tub has a built-in silent pump. If your hot tub is not equipped with one of these devices, it is recommended that you pump the water for a couple of hours a day to enjoy good, clear water.

Hot Tub Water Sanitization

The sanitization of hot tubs, is one of the most critical aspects of water chemistry. The two most popular sanitizers used are bromine and chlorine. To prevent the tub from becoming dirty, clean it with a simple granular disinfectant solution at a much higher concentration than normal. Then, allow the sanitiser to naturally fall to the level for safe usage.

The pH level is an important factor in sanitization. For hot tubs, the optimal pH range is 7.2 to 7.8, which is not only more comfortable on the skin, but also the range where bromine and chlorine are most effective. If the pH gets out of control, your hot tub will become murky because the sanitizer can no longer be effective. An easy way to avoid this problem is to monitor the water periodically and change it regularly.

Using a Clarifier

Clarifiers such as the pure clarifier are an additive that you can use as a solution to problems with murky water, even during your regular maintenance. Clarifiers work by combining small particles that are too fine to be filtered. When the particles bind together, it is much easier to remove them from the water cycle.

In general, it is recommended to use a clarifier once a week as part of your regular maintenance program, especially if the water tends to become murky. Follow the manufacturer’s instructions on the bottle. Generally use 2 oz. with a liquid clarifier. Use 500 gallons of hot water in the tub according to a weekly schedule. If you are trying to solve a major problem with murky water, double the dose.

We must add here that clarifiers are somewhat of a temporary solution and the underlying problem needs to be addressed.

Refill the Tub

Often the only way to repair murky water is to refill the hot tub. This should only be a total last resort. However, if you empty and refill the hot tub, you may find that the problem is in the fill water, which can be very rich in minerals. If you think this may be a problem, try measuring the total hardness of the fill water before pouring it in.

If this is the case (or if you simply want to save time by balancing the water), consider using a pre-filter. Pre-filters are attached to the end of the hose to do just that – remove minerals that would otherwise be trapped in the water to block the hot tub filter. This could be your biggest problem, and in the future you could have less murky water.

How Keep Murky Hot Tub water from Coming Back

What is the best way to repair the murky water in the hot tub? Firstly, keep it from happening. To keep murky hot tub water at bay here are the best practices to follow:-

  1. Pour the filtered water into the clean hot tub. This is super easy to do with a bag filter.
  2. Create and follow a daily maintenance schedule to keep your water clean and safe.
  3. Keep your filter clean and repair it if necessary.
  4. Clean the tubing of your hot tub with a washing liquid and check for biofilm each time you change the water.
  5. Test the water before adding chemicals. After you add chemicals, test it. And then test it again before you get in the tub. Find out anyway!
  6. Change the water every three or four months, or more often if there are problems.

Final Thoughts

In conclusion, check the filtration, drainage and plumbing systems if your hot tub water has become murky. Monitor the chemical levels too. The the chances are they are out of balance. If you continue to maintain your hot tub chemicals and filtration correctly, the murky water will be a thing of the past.

Happy Tubbin’

Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi


Hi, Andi here. I own and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Today, I've helped over 1000 DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi

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