Can You Get Rid of Biofilm Without Draining a Hot Tub?

rid of biofilm without draining lg

So, you’re looking forward to a good soak in your hot tub, but you notice a discoloration of the water or a bad smell. This can be a sign of biofilm build-up in your plumbing. But can you get rid of biofilm without draining a hot tub?

Here’s what I’ve done:

It is possible to get rid of biofilm in a hot tub without draining. Adding 1 gallon of white vinegar to the water can kill biofilm (but will also lower the pH). Adding extra chlorine will be ineffective in removing biofilm. But preventative maintenance every time the hot tub is drained is the best solution.

But that’s just a quick answer.

So, in this article, we’ll look at how to prevent biofilm in the first place too. And we’ll go step-by-step on how to get rid of biofilm with vinegar, including how much to add, and how to then adjust the pH.

And we’ll look at other possible methods for eliminating biofilm, most of which can be done without draining the hot tub.

Let’s get into it!

Ready to Spend Less Time On Maintenance and More Time Enjoying Your Hot Tub?

Let’s face it. Balancing the water, cleaning filters, dealing with rashes, and trying to figure out which chemicals to buy and add can make you feel more like a chemist than someone who just wants to relax after a long hard day!

That’s exactly why The Hot Tub Handbook and Video Course is so valuable!

This is from Matt over at Swim University and he developed it for people looking to save money, time, and frustration. His tips on chemicals can save you $100/year just by making sure you buy only what you need.

So if you’re ready to stop being confused or frustrated with your hot tub and start spending more time in it, check out The Hot Tub Handbook and Video Course.

Just click that link to learn more on their website.

What does biofilm look like in a hot tub? 

Biofilm is a greasy, slimy substance that builds up inside the pipes and is present on the filter(s). It is made up of all the dead skin, sweat, and oils from body lotions, deodorants, and perfume. But it is rarely seen unless there is a significant amount in a hot tub. 

So in most cases, you don’t really see biofilm; you just see the effects of it.

Cloudy or smelly water is a sure sign that something is wrong. This might be caused by a chemical imbalance, which can easily be checked using test strips, but often, it is down to a buildup of biofilm in the plumbing.

You may also see foam on the surface of the water, which is also a sign of biofilm presence.

Shocking with chlorine is one way to get rid of the foam and kill bacteria in the water. But chlorine alone won’t kill the biofilm. Regularly adding a sanitizer such as chlorine or bromine must be a part of your maintenance regime.

You should wait 20-30 minutes before getting into a hot tub after applying a regular dosage of chlorine. After shocking the water, leave it for 2-4 hours to allow the chlorine to dissipate. 

I wrote about this in a recent article. But there’s also a time difference between chlorine shock and non-chlorine shock. And will running the jets disperse it faster?

Just click that link to read it on my site.

Does vinegar kill biofilm in a hot tub? 

Vinegar can be used to kill biofilm in a hot tub as vinegar (acetic acid) is known for its antimicrobial effect on bacteria. However, it will also lower the pH, requiring a pH increaser to be added afterward.

(source)

Vinegar has many uses for a hot tub owner.

As an acid, it can be used to lower alkalinity and pH levels in the water, and as a cleaner, it works great at removing grease and grime. 

White vinegar is made from acetic acid and water.

It is less pungent than other types of vinegar, and being clear, it doesn’t stain the surface. Other types of vinegar can still work but won’t be nearly as cost-effective, and if they are a lower percentage (white vinegar is often 5%), it also won’t be as effective.

The best product to use in your hot tub is Lucy’s Distilled Vinegar (click on the link to check the current price on Amazon). This product is 5% white vinegar distilled with water to provide a consistent, stain-free cleaning agent.

With a score of 4.8 out of 5 from over 1,400 customer ratings, this is one of the best cleaning products out there, and being natural and free from added chemicals, it is good for the environment too.

How much vinegar should I add to my hot tub to kill the biofilm?

Add 1-gallon of white vinegar to the hot tub’s water and allow it to circulate with all jets and water features on for 2-hours. This will be an appropriate amount for all medium to large-sized hot tubs. For small 2-3 person hot tubs, add approximately 1/2 gallon of vinegar.

As the jets and water features time out, simply restart them. 

Leave the cover off during this time.

Also, with a 50/50 water and vinegar solution, wipe down the exposed parts of the acrylic shell and the underside of the cover. This helps ensure any possible biofilm on those surfaces is also killed.

CLICK HERE to check the latest price of Lucy’s White Vinegar on Amazon.

How to adjust the pH after adding the vinegar to your hot tub

Adding a gallon of vinegar to a medium or large-sized hot tub will lower the pH of the water by quite a bit.

Before adjusting the pH, after the water has circulated with the vinegar for 2 or more hours, test the water with a test strip to see where the pH is.

Adding that much vinegar can potentially lower the pH of your hot tub down to about 5.0 (the normal range is about 7.2-7.6).

But always test the water and adjust based on the readings rather than making assumptions.

But to adjust the water up to the mid-7 range from about 5.0, plan to add about 3/4 cup of a spa up or pH up type product. But if your spa up product is sodium bicarbonate, it will likely take a lot more than that.

Some spa-up products are just plain old baking soda. This will be labeled as sodium bicarbonate but it’s the exact same thing as what’s in the orange box in your kitchen pantry.

However, this significantly raises alkalinity much more than it does pH. So for our purposes here, it’s not the best way to go.

But when adding any hot tub chemical, always start with a smaller amount, allow it to circulate, and then test again in 20 minutes. You can always add more. But if you overdo it, you’ll have to wait a day for the levels to drop or then add a spa-down product.

My favorite product for raising the pH in a hot tub is this one by Leisure Pool on Amazon.

Many spa up products are made from soda ash, including the 1 I just linked to. But this can also cause the water to get a bit cloudy (especially in this large amount). But if the water smells fine and the levels all check out, don’t sweat it too much.

You can always add a double-dose of chlorine shock and wait a day before using which can help to clear the water.

Also, a word of caution.

Don’t leave a hot tub with low pH or use it. Low pH can not only corrode the metal parts in a hot tub over time but it can also lead to hot tub folliculitis or legionella (commonly called Legionnaires’ Disease).

This is because a low pH level means the water is highly acidic. Highly acidic water can neutralize the chlorine or bromine you use as sanitizer. And no or low sanitizer means over time your water can get dangerously high levels of bacteria.

So do pay attention to the pH and adjust as needed.

Can you use a hot tub with biofilm?

A hot tub with a high level of biofilm should not be soaked in as it can be unsafe. The best practice is to use a biofilm remover every 3 months when the water is drained and refilled anyway, as this will ensure no biofilm is ever-present in the hot tub.

Hot tubs provide the ideal environment for bacteria to develop, and this can lead to diseases such as folliculitis and Legionella.

In a recent article, I discussed how to get rid of folliculitis.

Legionella is far more serious but extremely rare and almost an impossibility if sanitizer is used on a regular basis. But there is 1 way it can still happen in even the best maintained hot tubs.

Just click that link to read it on my site.

Adding chlorine is the most popular way of killing off the bacteria in the water, and you should maintain a level of 1 to 3 parts per million (ppm). As a guide, if you have a 260-gallon hot tub that’s around ¼ ounce or 1½ teaspoons of granules every 2 or 3 days.

In a recent article, I talked about how often you should put chlorine in a hot tub.

But I also got into whether bromine is better and some of the key differences between the 2. I also spoke about powder vs. tablets in a floater.

Just click that link to read it on my site.

How do I know if I have biofilm?

The clearest signal of a biofilm problem in a hot tub will be the need to add larger amounts of sanitizer more frequently than it had been added previously to maintain a normal level. Biofilm develops in all hot tubs over time if no biofilm treatment is used.

But unless the problem is really bad, you won’t see it.

Even if everyone showers before getting in, they still bring their sweat, flaking skin, and hair. This combines with bugs and other organic matter that falls into the hot tub to create a slimy film.

This is where the bacteria build-up makes the water cloudy and smelly, so first, you have to kill off the bacteria, and you do this by adding sanitizer such as chlorine to the water.

I covered this in a recent article, but there’s a difference between bacteria build-up in the water and biofilm, which is bacterial growth on surfaces. And you have to treat the 2 very differently.

Just click that link to read it on my site.

The usual signs of heavy biofilm build-up are cloudiness, smelly water, and a layer of foam on top. You may have just one or all three signs present, but in any case, you know you have a problem.

Always start by checking the pH and alkalinity levels before doing anything else. 

If these are fine, you can eliminate this as a possible cause. Next, you should shock the water to see if this clears up the problem. If that fails, then you have a biofilm build-up to deal with.

How do I prevent biofilm in my hot tub in the future? 

The best way to prevent biofilm build-up is to add Oh Yuk! Healthy Hot Tub Cleaner to the water prior to draining. Allow it to circulate with the jets for 1 hour and then drain. Rinse, wipe down, and refill. Then repeat this process every 3 months.

CLICK HERE to see Oh Yuk! Healthy Hot Tub Cleaner on Amazon.

The average hot tub owner using chlorine or bromine will change the water every 3 or 4 months if proper maintenance is kept up, but those using salt water can go as long as 12 months without a change.

But either way, when the time comes, this is a great opportunity to give the surfaces of your hot tub a thorough clean and flush out the pipes and jets to prevent biofilm building up.

Again, I would highly recommend Oh Yuk Healthy Hot Tub Cleaner – you can check out the current price on Amazon by clicking on the link. That is the exact product I use and I use it every 3 months.

Use Oh Yuk in 5 easy steps:

    1. Remove the filter – this should be left to soak for 3 or 4 hours in a 50/50 white vinegar/water solution.
    2. Add 8oz of Oh Yuk to the water.
    3. Keep the jets running (restarting them as needed) and allow the water to circulate for 1 hour.
    4. Turn off power to the hot tub
    5. Drain the tub and wipe down the surfaces with an all-purpose cleaner and a cloth. Windex or Lucy’s Distilled Vinegar are great for this.
    6. Give a quick rinse of the shell with the hose
    7. Use a wet/dry vac to suck up any excess water
    8. Refill the tub in your usual way.
    9. Turn the power back on once the water level is above the jets
    10. Rinse the filters and put back in the hot tub

Doing this every time you change the water will go a long way to preventing a biofilm build-up.

CLICK HERE to see Oh Yuk! Healthy Hot Tub Cleaner on Amazon.

Did I cover all you wanted to know about getting rid of biofilm without draining a hot tub?

In this article, we looked at how to identify a biofilm problem.

But we also looked at how to get rid of it, and how to prevent it in the first place. This is something every hot tub owner has to face at some point.

Ready to Spend Less Time On Maintenance and More Time Enjoying Your Hot Tub?

Let’s face it. Balancing the water, cleaning filters, dealing with rashes, and trying to figure out which chemicals to buy and add can make you feel more like a chemist than someone who just wants to relax after a long hard day!

That’s exactly why The Hot Tub Handbook and Video Course is so valuable!

This is from Matt over at Swim University and he developed it for people looking to save money, time, and frustration. His tips on chemicals can save you $100/year just by making sure you buy only what you need.

So if you’re ready to stop being confused or frustrated with your hot tub and start spending more time in it, check out The Hot Tub Handbook and Video Course.

Just click that link to learn more on their website.


Image by Arek Socha from Pixabay Image by Nina Garman from Pixabay

Jeff Campbell

Jeff Campbell is a husband, father, martial artist, budget-master, Disney-addict, musician, hot tub lover, and recovering foodie having spent over 2 decades as a leader for Whole Foods Market.

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