Understanding Biofilm in Hot Tubs
Recently, some news headlines have shone an unsavory light on the potential health risks of an unmaintained spa. Much of the concern centers around biofilm in hot tubs, an issue that many people don't fully understand. News stories and images showing bacterial blooms or folliculitis have only added to the confusion, often without explaining what biofilm is or how it forms in a hot tub environment.
The truth is, hot tub ownership does require regular upkeep—not just for aesthetics but for your health, too. Maintenance is essential to prevent the buildup of harmful substances, including hot tub biofilm. However, some hot tub owners, especially new ones, may not be fully aware of how to deal with this issue. So, what is biofilm, and why is it such a problem in hot tubs?
What Is Biofilm in a Hot Tub?
Biofilm is a sticky, slimy layer of organic material that forms when bacteria and other microorganisms attach themselves to surfaces and produce a protective layer. In a hot tub, this often happens in the plumbing lines, where the warm water creates the perfect breeding ground for bacteria. The problem is exacerbated because biofilm in hot tubs prevents chemical sanitizers like chlorine and bromine from effectively killing the bacteria beneath it. Essentially, it acts as a shield, allowing bacteria to thrive while remaining hidden from sight.
But what does biofilm look like in a hot tub? You'll often notice a thin, greasy layer floating on the water’s surface or clinging to the walls of the tub. In more severe cases, biofilm in a hot tub may manifest as brown slime in the hot tub or cause foamy, discolored water during cleaning processes.
The First Step: Draining Your Tub on a Regular Basis
You should be draining and refilling your hot tub water every 3 months. Why?
First, there are used sanitization chemicals. When chlorine or bromine comes into contact with bacteria in the water, it naturally morphs into a stable form of sanitizer. These fragments are no longer able to kill bacteria. Instead, they cause chloramines which are easily identified by a strong chemical smell emanating from your water.
Second, your hidden plumbing lines are home to a thriving bacterial playground. It has been discovered over 95% of all hot tub bacteria does not live floating in the water or adhered to the shell. Instead, the bacteria resides in your pipes, beneath matter called biofilm. Biofilm is best described as a “sticky, tar like layer” preventing your chemical sanitizers from reaching the underlying bacteria. Biofilm is noted for causing the dreaded itchy red bacterial blooms, and in acute cases, folliculitis.
Why Draining Your Hot Tub Isn’t Enough
One of the biggest mistakes hot tub owners make is assuming that simply draining and refilling the tub will solve their problems. Unfortunately, this doesn’t remove biofilm from hot tubs. In fact, as you drain the tub, most of the bacteria that were hiding in the biofilm stay lodged in the plumbing system, only to be transferred right into the fresh water during the refill. Yuck!
The only way to remove biofilm from a hot tub effectively is by performing a line flush. This involves running a specialized cleaner through the plumbing system to break down the biofilm, allowing it to be flushed out with the water. Failing to do so means you could still have dangerous bacteria lurking in your hot tub, even after a thorough cleaning.
How to Identify and Treat Biofilm in Your Hot Tub
You may be wondering, “What causes biofilm in hot tubs?” The answer is a combination of factors: warm water, poor maintenance, and inadequate chemical treatments can all lead to the formation of biofilm. So, what are the signs of biofilm in a hot tub? Common indicators include cloudy water, a slimy or greasy feeling on the tub’s surfaces, and persistent chemical imbalances. If you notice any of these signs, it’s time to act fast before the problem gets worse.
One common question is, "Does vinegar kill biofilm in hot tubs?" While white vinegar is often used to clean the shell of the tub, it isn’t powerful enough to penetrate the biofilm in the plumbing lines. To properly clean hot tub biofilm, you’ll need a line flush cleaner designed specifically for this purpose. These cleaners circulate through the plumbing system, breaking up the biofilm so it can be drained away.
Once the line flush is complete, and the water has been drained, you can use a white vinegar and water solution (one part vinegar to four parts water) to scrub the shell. This helps sanitize the surface, but it’s crucial to address the plumbing lines as well.
Is Biofilm in Hot Tubs Dangerous?
The next question on many hot tub owners’ minds is, “Is biofilm in hot tubs dangerous?” The short answer is yes. Left unchecked, biofilm in a spa can lead to several health problems, including skin infections, rashes, and even respiratory issues. The bacteria harbored within the biofilm can cause conditions like folliculitis, which manifests as red, itchy bumps on the skin after soaking in contaminated water. This is why regular maintenance and thorough cleaning are critical for keeping your hot tub a safe, relaxing environment.
How to Get Rid of Biofilm in Hot Tubs: A Step-by-Step Guide
Now that we’ve explored the basics of hot tub biofilm, we arrive at one of the most popular questions spa owners have on this topic: “How to get rid of biofilm in hot tubs?” Here's a step-by-step process for ensuring your hot tub stays biofilm-free:
Remove the Filter: Start by removing the filter from the hot tub. This allows the line flush cleaner to circulate freely through the plumbing system.
Add a Line Flush Cleaner: Pour a biofilm remover or line flushing product into the water. Be sure to follow the manufacturer’s instructions regarding the amount to use and how long to let it circulate. In most cases, the cleaner needs to run through the system for 30 minutes to 5 hours, depending on the severity of the biofilm buildup.
Monitor the Water: Don’t be alarmed if the water turns cloudy or foams up with black or brown debris. This is a sign that the biofilm is breaking apart and being removed from the system. In cases where a hot tub has not been properly cleaned in a while, you may see a substantial amount of debris surfacing during this process.
Drain the Water: After the cleaner has done its job, drain the water using the hot tub's built-in drain or a sump pump. This will remove the broken-down biofilm and other contaminants.
Clean the Shell: Once the tub is drained, it’s time to wash the interior shell surface. Use a white vinegar and water solution or a specialized cleaner to ensure all residue is removed.
Refill and Balance: After cleaning, refill the hot tub with fresh water. Be sure to test and balance the chemicals before using the tub again.
This process should be done every three to four months to ensure your hot tub remains free of biofilm and other contaminants. If you’re unsure how to clean hot tub biofilm, consult your hot tub’s user manual or contact a professional.
Maintenance Tips to Prevent Biofilm Buildup
Preventing biofilm in hot tubs starts with regular maintenance. Always follow recommended guidelines for chemical balancing and water changes. Using a line flush cleaner regularly can help keep the plumbing lines clear of biofilm, and keeping a maintenance log is a simple but effective way to stay on top of your cleaning routine.
In addition to regular line flushing, be sure to clean the hot tub’s filter often. A dirty filter can contribute to biofilm buildup by allowing contaminants to circulate through the water. Lastly, always shower before entering the hot tub to wash off oils, lotions, and other substances that could promote the growth of biofilm.
By taking these precautions, you’ll not only prevent biofilm buildup but also prolong the life of your hot tub’s components and maintain a clean, safe environment for soaking.
