How To Fix Hot Tub Biofilm Or Other Foul Contamination

Have you noticed an increase in chemical levels in your spa or hot tubs? If so, it may be because of hot tub biofilm buildup. Biofilm, sometimes referred to as spa bacteria, is the slime layer that forms on the surfaces of water pipes, hot tubs, and other water-containing environments. Biofilm accumulation can cause a spa to become cloudy and unable to filter water properly. It can also lead to a hot tub itch, rash, and equipment damage.

hot tub biofilm
Fix hot tub biofilm or other foul contamination

To fix hot tub biofilm, it is helpful to understand the problem and know how to clean it properly. So cleansing biofilm from your spa's plumbing with hot tub cleaner instruments may be the best way to start restoring balance and clearing up any contaminants. Keep reading to learn more about Biofilm and how to fix it.

What is hot tub biofilm buildup?

Hot tub biofilm is a slimy growth layer of microorganisms that can build up on the surfaces of hot tubs and spa baths. The buildup is caused by bacteria and other microorganisms that thrive in warm, moist environments. While some biofilm is inevitable, it can become a problem if it starts to interfere with the performance of the spa. For example, Biofilm can clog filters and pipes, reducing water circulation and increasing maintenance costs.

In addition, Biofilm can provide a breeding ground for harmful bacteria, posing a risk to human health. Fortunately, there are several steps that hot tub owners can take to control biofilm growth, including regular cleaning and disinfection. Taking those precautions can help keep your hot tub or spa looking and functioning at its best.

Problems that Biofilm Causes for Hot Tub Water

As we mentioned before, One of the most widespread problems with hot tubs is the buildup of biofilm slime. This slimy substance is caused by various bacteria that grow and multiply in warm, moist environments.

If left untreated, biofilm can cause severe damage to your hot tub plumbing lines and filters. Biofilm can cause several problems in hot tubs, including:

  1. The buildup of biofilm can lead to the growth of harmful bacteria, which can make people sick.
  2. The biofilm effect leads to the formation of scum and algae, which can make the water look and smell bad.
  3. Biofilm can clog up filters and other equipment in the hot tub, causing it to work less efficiently.
  4. Biofilm can also increase the likelihood of corrosion in the spa plumbing system.
  5. In extreme cases, biofilm can cause the spa system to fail.
  6. The protective slime layer of biofilm is challenging to remove and can require extensive cleaning procedures.
  7. Biofilm is often resistant to traditional disinfectants, so it can be hard to eliminate it.
  8. The use of biofilm-promoting chemicals (like chlorine) can exacerbate the problem, making it even harder to eliminate the biofilm.
hot tub biolfilm is a problem of the past
No more biofilm with O-Care

The hot tub itch

The hot tub itch is a condition that affects people who spend time in hot tubs. The main cause of the itch is not known, but it is thought to be caused by the chemicals in the water or the heat of the tub. The itch can be anywhere on the body but is most commonly found on the torso and legs.

The Hot Tub itch, also called Pseudomonas aeruginosa, is a skin infection caused by bacteria. The bacteria thrive in warm, moist environments and can be found in hot tubs, swimming pools, and water parks. Symptoms of the Hot Tub itch include redness, rash, itching, and blisters. This type of infection can be treated with antibiotics, but it is important to seek medical attention if symptoms occur.

Side-effects of hot tub rash:

Is hot tub biofilm harmful to equipment?

Yes, it's harmful to equipment. Hot tub biofilm is a slimy, bacteria-laden film that can form on surfaces in your spa's equipment and plumbing. If left untreated, this biofilm can increase the risk of continuous water contamination, plumbing, and filtration system. While it is not harmful to humans, hot tub biofilm can harm your spa's equipment.

To prevent the formation of hot tub biofilm, it is essential to keep your spa clean and free of organic debris. Be sure to clean all surfaces regularly with a mild detergent or chlorine bleach solution. It would help if you also shocked your spa weekly to kill any bacteria in the water.

How do I know if I have biofilm?

The best signal for biofilm problems is adding more sanitizing fluid than was previously needed to maintain normal water chemistry levels. A Biofilm may develop anytime in the hot tub without any biofilm treatment.

How To Fix Hot Tub Biofilm Or Other Foul Contamination
Clear water thanks to O-Care

However, a problem will never appear until you have a terrible situation. Even if all people get out of the shower before entering, they bring body oils and dead skin cells. It's mixed in with bugs in the bath to produce the slimy film of the bath water. This can cause water to cloud and stink. Then you must destroy bacteria first and add a disinfectant like chlorine to the water.

How to get rid of biofilm contamination in the hot tub

Contamination that can only be killed with a sanitizer is one of the biggest underlying problems that can cause many issues. If you suspect you have a biofilm issue, the easiest way to get rid of it is by shocking the system with a high chlorine concentration. This will kill the bacteria and break down the biofilm.

You can also use a hot tub enzyme cleaner to break down the biofilm and organic matter causing the contamination.

By following these steps, let's try to eliminate as much contamination and bacteria as possible.

Steps to Get Rid of and Prevent Biofilm

1: Purge the Hot Tub's Plumbing System

First, ensure the hot tub is clean on the inside by purging the system with a tube cleaner. Many in-system cleaners are on the market because they can be generic products. You can try one that suits you from your local spa store.

2: Clean or Replace the Filter

Clean the filter, or even better, you can replace it with a new one. You should clean the filter every week and, on average, replace the filter yearly, depending on hot tub usage. Please consult your manufacturer for the replacement frequency. Filtration is 50% of sanitation, meaning you need fewer chemicals and sanitizers if you have a clean filter. Because the filter will get saturated and will hold bacteria which is contamination, you will need to make sure this is clean or replaced.

3: Check for Hot Tub Contaminations

When you have cleaned and refilled the hot tub, we can now check if most or all of the contamination has gone from the system. To do so, we will need some chemicals:

Choose a sanitizer such as

4: Before getting back into your spa water

Before you start using the hot tub:

  • Add 120 Gram or 4.2 Ounces of Non-Chlorine Shock (Monopersulfate / MPS).
  • Wait one day, then add your preferred sanitizer and the amount indicated on the packaging.
  • Wait 3 hours at least before you use the hot tub after this.
  • Measure and bring them to the required level (see graph below). 

If everything is at acceptable levels, you're back in an ideal environment for you to use your hot tub. Your water will once again kill bacteria and stop biofilm building up.

Chemical levels still not at acceptable levels?

You will need to take action if you are not measuring acceptable water chemistry levels.

Repeat the steps listed in point 4 with the mentioned steps above.

Because there is still contamination in the hot tub, the sanitizer is being "used up". The reason for adding more Non-Chlorine Shock (Monopersulfate / MPS) is to eliminate that. Non-Chlorine Shock (Monopersulfate / MPS) will oxidize contamination but DO NOT USE THE HOT TUB when you've added the product in this higher amount. You will need to wait at least a day, as mentioned in step 4 above.

How do I prevent biofilm in the future?

Biofilm is a bacteria buildup that can form on any surface in contact with water. In hot tubs, biofilm can cause problems such as foul odor, slime deposits, and reduced water quality. However, the O-Care app shows you step-by-step how to fix water problems.

This free app can be downloaded from the App Store or Google Play and can be used on both phones and tablets. The app is so easy to use and understand because it shows you why something is wrong with animations. With the O-care app, you can learn more about biofilm prevention ways.

water rich environments
Prevent biofilm with O-Care

So going through the steps one by one, it's easy to fix the water problem.

To help prevent Biofilm from developing in your hot tub, there are a variety of things you can do:

1. Balance water chemistry - Regularly test and adjust pH, total alkalinity, and calcium hardness levels. Maintaining the correct balance of these chemicals will help to prevent the formation of Biofilm.

2. Clean filters regularly - Dirty filters can provide a breeding ground for bacteria, so it's important to clean them often. Agin Purify the Spa Once the spa has been completely drained, the interior surfaces will be cleaned. A soft cloth should easily remove dirt from the hot tub shell.

3. Drain the water after 2 to 3 months - Draining your spa and refilling it with fresh water every few months will help to keep the water clean and biofilm-free.

4. Cover your spa if you don't use it - This will help to keep out debris and contaminants that can contribute to the formation of Biofilm.

5. Consider using a Water Care Monitor - A Water Care Monitor such as the O-Care app can help you track your spa's water chemistry and ensure that it stays balanced, which will help prevent biofilm from forming. However, The plumbing and filtration system of hot tubs provide an ideal environment for the growth of biofilms.

Resources to keep your hot tub clean

  1. Download the O-Care app for weekly maintenance and step-by-step problem-solving.
    1. Use our online water assistant to diagnose your water quality issues.
    2. This article covers more situations if the app didn't help solve your problem.
  2. I need to solve an underlying contamination issue in my hot tub; maybe it's biofilm?
  3. How to avoid future problems and keep your hot tub clean?
  4. What kind of sanitizers can I choose from?
  5. What is the best way to maintain my hot tub water?
  6. How to test the water in my hot tub?
  7. All our latest O-Care blogs

FAQs about Hot Tub Biofilm

How do I get rid of biofilm in my hot tub?

You'll need to use a special antibacterial solution to clean and disinfect your hot tub. Start by filling a spray bottle with the solution and spraying it into the water. Leave the bottle in place for at least two hours to kill any biofilm that may be present. Afterwards, you can use a scrubber brush to clean the hot tub's surface.

How fast does biofilm develop in a hot tub?

Biofilm can develop quickly in a hot tub, often in as little as 48 hours. It means it is important to take measures to prevent its formation and growth, such as regularly cleaning the tub and using sanitizers.

Does vinegar kill biofilm in a hot tub?

Yes, vinegar can indeed kill biofilms in hot tubs. Vinegar is a chemical agent used for centuries to clean and disinfect various surfaces. In hot tubs, biofilms are formed as contaminants build up on the water's surface.

Biofilms are bacteria-based tissues forming on surfaces with chlorine and other chemicals. Acetic acid, which is present in vinegar, destroys biofilms by dissolving their protective layer. This allows the chlorine and other chemicals to damage and kill the bacteria lurking within the biofilm.

How do I eliminate biofilm in my inflatable hot tub without draining it?

The easiest way to get rid of biofilm in an inflatable hot tub is to use a chlorine tablet or granular chlorine. Dissolve the chlorine in a gallon of water and pour it into the hot tub. The Biofilm will be killed, and the water will be sanitized. So follow the manufacturer's instructions when using this product, as too much chlorine dioxide can be harmful.

Wrapping Up Hot Tub Biofilm

Biofilm is a sticky film with a protective layer that can build up on the surfaces of water systems, including hot tubs. This Biofilm can cause several problems, including hot tub itch, rash and even water system equipment damage. Keep your hot tub clean and free of biofilm to prevent these problems. Follow the instructions in this blog to rid your hot tub of biofilm and enjoy clear water for years to come! To make your hot tub maintenance even easier, try O-Care!