What Causes Scum Lines in Hot Tubs

As an Amazon Associate I earn from qualifying purchases.

What Causes Scum Lines in Hot Tubs

Most of the time, we are keen when doing our house chores. Although this is the case, we can slack a little with the chores as they are repetitive. Some of these chores include cleaning your bathroom and especially your hot tub.

Hot tub maintenance is essential as it prevents the build-up of scum rings on the shell and oily scum on the water. Knowing what causes scum lines in hot tubs is essential, as it will help prevent the formation of the common scum on your hot tub. 

spa shock

Spa Choice Re-Energize Oxidizing Spa Shock

  • Quickly oxidizes contaminants
  • Enhances the sanitizing effectiveness of chlorine and bromine
  • Removes chloramines and bromamines that cause chlorine odor
  • Non-Chlorine Shock

Types of Hot Tub Scum

Before we dive into the causes of what causes scum lines in hot tubs, let us look at hot tub scum types. 

1. Blue-Green Scum 

This type of scum is considered one of the most difficult to remove, let alone prevent. This is because it is a result of various dirt particles. The dirt particles include secretions from the human body, metals, personal care products in water, a worn-out filter, or a filter that has not been well cleaned. When you have all this dirt in your tub, it leads to the formation of this type of hot scum. 

2. Green Scum

What happens to an old penny is the same thing that causes this type of scum. An old penny develops green scum due to its high copper content. If you notice green residue in your bathtub, your water has a high copper level. Therefore, the hot water tub quality is vital to reduce the formation of this scum. 

3. Brown Scum

The pH level in your water can also lead to the formation of scum lines. This means if the pH level is very high, a chemical reaction makes minerals in the water react. For instance, iron can react with chlorine, leading to the formation of a nasty brown scum on the water’s surface. Moreover, one can also find this sticky scum at the surface of your bathtub shell. 

Friends Relaxing in a Hot Tub

What Causes Scum Lines in Hot Tubs

Hot tub water filters help remove chemicals, dust, and debris before the water enters your tub. But, sadly, a water filter can only do enough for so long. In addition, if the water pollutants are not removed for some time, or you have not taken any appropriate measures to remove the debris, the pollutants can form a layer of scum that floats on the water surface or forms a ring on the hot tub shell. 

Let’s take a look at the causes of hot tub scum:

1. Metals

Dissolved metals are present in the water in your bathroom. It is important to note that all water has some metals in it. These metals include chromium, copper, lead, magnesium, and iron. The concentration of these types of metals is dependent on where you live. For example, if you use water pumped from a well, there is a higher metal concentration. The concentration can also be higher if you live in the city.

All tap water has chlorine, which means even the water in your tub has chlorine. When the chlorine begins to react with the metals found in water, oxidation occurs. This causes staining on the tub’s shell. Take note that this oxidation can also lead to the formation of greenish scum in the water. 

2. Personal care products

There are a lot of products that we use on our bodies daily. These products include make-up, body oils, aftershave, deodorants, hair products, shampoo, and perfumes. When you don’t shower before taking a dip in the tub, these products are in your bathtub. The products stick on the surface of the bathtub leading to scum build-up.  

3. Bodily residue

Bodily residue is the most common cause of scum in the hot tub. Our bodies ‘shed’ off 30-40,000 dead skin cells each day. The first 18-23 layers of our skin consist of dead skin cells ready to be expelled. When you sit in hot bubbly water, you lose skin cells faster. 

In addition to losing the skin cells that end up on the tub’s surface, we also lose approximately 50-100 hairs each day. On top of that, our bodies have oils that rise to the skin’s surface. When we have our bathtub moment, the water is hot; our bodies lose some water and these oils through sweat. These bodily fluids are left on the surface of the tub. 

4. Worn out or dirty filter

A water filter’s task is to sieve any dirt that might contaminate your water. This ensures that the water quality of the bathtub tap is just right. Although this is the case, you will still notice some mild scum forming on your bathtub. This is why looking for a filter cleaner is essential in ensuring that no residues are left on the filter, making it inefficient. 

Take note that using a filter cleaner might not be enough; you will need to replace the hot tub filters altogether. 

5. Bad water chemistry

To ensure that your spa water is clean and healthy, you must keep the water in your tub balanced adequately. Imbalanced water has a lot of adverse effects on the state of your tub. When the water in your hot tub is imbalanced, especially when the alkalinity levels are high, it creates a welcoming environment for algae. High pH levels are also conducive for the growth of bacteria, which will lead to the formation of scum. 

Now that we know the types of scum and their causes, we must look at how to prevent hot tub scum lines. 

How to Prevent Hot Tub Scum?

First, you should go for a quick shower before entering the tub. It would be best always to do this as it will reduce the amount of bodily residue and skincare products left on the water. 

It is a no-brainer that eating or drinking in the tub is unhygienic. This is because some drink or food might fall or spill in the water tub, and this debris forms scum lines on your tub. If you have to eat, do it outside of the tub. 

Regular shock treatments are advisable for your water. For instance, you can use non-chlorine shock to remove the contaminants found in the hot tub water. However, note that when you opt for chlorine shock for your tub, the treatment will increase the chlorine level in the water. This is because chlorine reacts with other dissolved metals, creating scum. 

Cleaning the filters is also vital in scum prevention. Ensure that after using the hot tub, you clean the filters using a filter cleaner. In addition to that, one should replace any not working filter as soon as possible.

Another thing that you can do to prevent hot tub scum is by changing the water regularly. You should ensure that you change the water in your tub regularly. This means that the water in your hot tub should be drained down and refilled after every 12 hours. This is after you use it. Remember to clean the tub before you refill the water. 

Anyone who has a hot water tub in their home might have come across scum in their tub. Luckily, we have given you all the needed information to send that scum packing so that you can enjoy your next experience. Happy soaking! 

What Causes Scum Lines in Hot Tubs

Spa Choice Re-Energize Oxidizing Spa Shock

  • Quickly oxidizes contaminants
  • Enhances the sanitizing effectiveness of chlorine and bromine
  • Removes chloramines and bromamines that cause chlorine odor
  • Non-Chlorine Shock

Amazon and the Amazon logo are trademarks of Amazon.com, Inc, or its affiliates.

Similar Posts

Leave a Reply

Your email address will not be published.

I accept the Privacy Policy

This site uses Akismet to reduce spam. Learn how your comment data is processed.