Why Do Hot Tub Sponges Turn Brown?(Solved)

Do Lay‑Z‑Spa Hot Tubs Have Built-In Seats?

Why Do Hot Tub Sponges Turn Brown?

Tub sponges are a type of cleaning tool designed for quick and easy use, with a large sponge head on a rod.

The sponge has a rough texture that quickly removes clumps and pastes from most surfaces, including glass, tile, porcelain, plastic, drywall, and more.

This is because of improper water chemistry especially too much calcium, dirty water and lack of filtration. The calcium will usually deposit onto the sponges and eventually turns brown. You can quickly solve this problem by letting the water flow through a more robust filter, such as an undergraduate Filter.

To fix this problem, lower the calcium level in the water before trying anything else. It’s also essential to ensure that your hot tub has a filter to remove any calcium build-up properly.

They are also convenient to carry around in the bathroom or kitchen.

Here are other causes of brown hot tub sponges:

Dirty Water– If the water circulates through your hot tub and is dirty because there isn’t a filter, the sponges will eventually turn brown. Again, you can fix this problem by filtering the water properly.

Although you may think this is caused by too much calcium in the water, it’s usually not the case. If you notice an increase in pH and chlorine, that’s usually a sign that there isn’t any filtration currently taking place.

Lack of Filtration– If the problem lies in the fact that although your Spa does have a filter, all of the water is going through it and not filtering correctly, then you’re likely to get brown sponges.

This small device will help filter the water before it circulates through the heater and sponges, so you’re not getting brown ones.

How Do You Use a Sponge in A Hot Tub?

Place the sponge in any pool skimmer or free-float it in a Spa. Gently run the water on it to remove any dirt or other foreign particles.

You can also use it between bathers if you want to keep your tub clean. The sponge will absorb the excess water and help maintain a high-pressure level, making your hot tub last longer.

You can also use it to clean the filter. Sponge it off if debris stays in your tub after you empty it. You won’t have to worry about scrubbing or scraping because the sponge will eliminate any grime or unusual stains.

There are different types of sponges for hot tubs, like fiberglass sponges and scouring pads.

Professionals mostly use the latter, but fiberglass sponges are best suited for regular home use and on different surfaces such as acrylic, fiberglass, and tile.

You can also use a sponge to heat your hot tub. Once the water temperature reaches 100 degrees, use an electric heater and let it warm up.

The heater will turn on automatically once it gets to the proper temperature.

If you want to add or remove water from your Spa, use a sponge between bathers for the perfect fit. If you want to remove debris from your hot tub, use a fiberglass or scouring pad.

Is A Scumbug Just a Magic Eraser?

No! The ScumBug is not just a magic eraser. The ScumBug is more than just an eraser. It cuts through dirt and grime and helps remove fat, oil, grease, and paint while safely sanitizing upholstery surfaces and carpets.

You can use the ScumBug on all household surfaces, even delicate fabrics.

The ScumBug eliminates the need for harsh chemicals and toxic cleaners, which means no more harmful fumes or residues contributing to indoor air quality.

With a ScumBug in your home, you will always have an easy-to-use cleaning tool to rely on when dirt presents itself.

The ScumBug is eco-friendly and safe because it does not contain bleach and is non-toxic. It will save you loads of time, money, and effort. Just rub, scrub, sanitize, and watch the ScumBug do its cleansing magic.

The ScumBug is made from 100% recyclable material. The soft and flexible form makes it easy to use.

It is made from exclusive, patented material wear and discoloration are not an issue.

Oil Absorbing Sponges- 5 Best and Features

Scumbug-Improves Filtration  

-Absorbs an incredible 40x its weight in oil and pollen

-Cleans without the use of chemicals

-Easy to use and store

Scrubba Wash Bag-Cleans without chemicals, harmful ingredients, or water  

-Made of all recyclable materials

-Includes a drying rack for easy access when you need it most

Scumballs-Cleans without chemicals, harmful ingredients, or water  

-Made of all recyclable materials

-Includes a drying rack for easy access when you need it most

Zombie– Keeps your water sparkling clear  

– Use in conjunction with eco3spa or eco one Spa Monthly

-You can use it with Chlorine, Bromine, Aquafinesse, Spa Frog, O-Care, or any other spa sanitation system.

-Keeps your skin and hair soft and supple, resulting in less hair fall

-Promotes good health through poor circulation

ZOTEE Oil-Absorbing Sponge-Gently removes excess oil from the skin  

-Skin feels soft and elastic

-Cleans without chemicals, harmful ingredients, or water

-Made of all recyclable materials.

EcoONE Sponge-Improves filter cleaning efficiency by removing fine particles and excess oils, which can clog pores and cause acne breakouts.


-Cleans without chemicals, harmful ingredients, or water

-Made of all recyclable materials. Each sponge is individually wrapped in a clear bag for easy storage.

Wave Spa Star Eraser Oil Cleans without chemicals, harmful ingredients, or water


-Made of all recyclable materials. Each sponge is individually wrapped in a clear bag for easy storage.

-Improves filter cleaning efficiency by removing fine particles and excess oils, which can clog pores and cause acne breakouts.

How Do You Clean a Scumbug?

Detergents – Cleaning with a detergent is the standard method of removing scum. Detergents emulsify the oils in scum and act as a surfactant to reduce the surface tension on water molecules.

This enables it to dissolve fats and other protein-rich particles, enhancing its cleaning ability.

Solution Additives– Detergents bind with the scum and remove it from the water’s surface. However, this can only last for so long.

To prolong the effect of detergent in cleaning, you need to increase its concentration or use an additive.

These additives include alum (aluminum sulfate), sodium alginate, or super phosphate (natural powdered silica).

Oxidizers– Oxidizers are chemicals that produce oxygen as a side product when released.

This is a chemical reaction that creates oxygen, generally occurring through a process called oxidation (adding oxygen to the molecule).

Common oxidizers you can use in hot tub cleaning products include:

  • Sodium perborate tetrahydrate (an inorganic salt).
  • Sodium percarbonate (another inorganic salt).
  • Hydrogen peroxide.
Why Do Hot Tub Sponges Turn Brown?

Alkalinity Reducer– Another way of removing scum from the water is by reducing acetic acid or its organic form, ethyl acetate.

This chemical reacts with the fatty acids present in scum to form a drying agent known as acetic acid, which dries out the fat particles and further reduces the amount of scum.

Ozone -Ozone (O) is another chemical you can use in hot tub cleaning. It has a powerful oxidative effect on organic molecules, which allows it to oxidize scum quickly.

The oxidation process produces hydroxyl radicals, increasing the rate at which scum is oxidized.

This results in a cleaner water surface and fewer maintenance costs as you do not need chemical cleaners as often.

Ammonium Sulfate– Ammonium sulfate is a strong oxidizer. This chemical reacts with organic molecules in the water to produce free sulfur, which further catalyzes the oxidation process and removes scum.

When Should You Replace Oil-Absorbing Sponges?

Replace oil-absorbing sponges once they have absorbed enough oils. Oil adsorption sponges essentially get rid of oils and other contaminants by absorbing the oil.

They design them to save your hot tub from those unexpected messes you might run into. However, sponges are not designed to absorb other contaminants like bacteria or detergents.

You should replace your oil-absorbing sponges if their color changes significantly or they stop functioning correctly.

It would help if you replaced your oil-absorbing sponges once per season. This is because the oils and other contaminants absorbed during the last season begin to break down and fall apart over time.

So, with continued use, you will notice that their absorbency will decrease over time.

It would help if you replaced your sponges no matter what because they do get dirty and eventually stop functioning properly. However, replace them every season to keep them in top shape.

Each sponge holds about one ounce of oil. So, you should be able to get about 80 sponges from one pound of hot tub oil. Oil-absorbing sponges are available in sizes from one ounce to two ounces.

If the size of your hot tub is between these two categories, you can get the proper sponge for your needs by ordering them online or in person.

Can You Reuse Hot Tub Sponges?

Yes! You can reuse Hot tub sponges. It would help if you wash and rinse them after every use and store them in a clean, airtight bag or container when not in use. To wash the hot tub sponges:

  1. Rinse the sponges in hot water.
  2. Use mild soap or detergent to remove any dirt, debris, and oils.
  3. Rinse until water runs clear.
  4. Let air dry or tumble on high speed for 10 minutes.
  5. Store in a clean, airtight bag or container.
  6. Use a new sponge for each use.
  7. Replace the hot tub sponges once a month or as needed if heavily soiled.
  8. If using hot tub chemicals, rinse the sponges to kill bacteria but do not let water remain on the sponges overnight. This can cause pitting on the sponge surface and affect its ability to clean effectively.

Use cold water to rinse and air dry or tumble dry after each use to prolong the life of your hot tub sponges.

Can You Make A DIY Oil-Absorbing Sponge?

Yes! It’s simple and cheap. All you need is two ingredients:

-Dish soap

-Cotton pads

Pour the dish soap into a bowl, then place the cotton pads. Swirl them around to soak up as much liquid as possible. Remove the pads from the bowl and let them dry for 24 hours.

You should refrain from soaking the cotton pad again. If they get wet again, they will lose more oil and become more absorbent.

You can use the sponge multiple times, but the oil will eventually build up and no longer absorb any liquid. Therefore, you will need to make a new sponge occasionally.

Why Do Hot Tub Sponges Turn Brown?

It’s essential to wash the sponge periodically to remove the built-up oil, or the cotton pad will become saturated with oil and odorless (or barely noticeable).

This sponge is helpful because it can easily wipe your hands without needing a germ mask. You can use it to clean a counter or bench, as well as you use for cooking oil.

This oil sponge is also a good alternative for germ masks, such as hand sanitizer. You can leave the sponge under running water for about 10 minutes to eliminate the excess oil.

You can also use a paper towel or napkin that contains alcohol, but it will be difficult to remove the oil.

What Does Biofilm Look Like in A Hot Tub?

Biofilms look like thin, hairlike mats of bacteria on surfaces. They can form on many water-saturated surfaces in your home or workplace, including bathtubs, showers, sinks, washing machines, and dishwashers.

For most people with healthy immune systems, the presence of biofilms is not a problem.

However, for others who are immunocompromised or have impaired immune systems due to chronic illness or age, biofilms can cause serious health problems.

These infections occur because biofilm bacteria act like a shield protecting them from the immune defense systems of your body. In addition, some biofilm-forming species produce toxins that cause tissue damage and inflammation.

Unfortunately, biofilms are most often not visible to the naked eye. The best way to detect a biofilm is with an electron microscope.

Biofilm bacteria have several different ways of spreading throughout your home or workplace. They can travel between surfaces on people’s hands, skin and hair follicles, or clothing.

Airborne particles and water droplets containing bacteria can also spread the biofilm.

Biofilms are common in hospital settings with high levels of hygiene and sanitation. This is because biofilms can have difficulty spreading when germs are present in the environment.

The presence of water, soap, and disinfectants can prevent biofilms from spreading by causing them to adhere or dissolve away.

Why Are My Chlorine Tablets Not Dissolving in The Floater?

Poor check valve in the chlorination system– This prevents water from flowing back out of the system and into the pool.

Leaking filter canister– This will cause unregulated water to flow into the pool, releasing chlorine slowly and gradually, reducing residual levels and eventually leading to a chlorine shortage.

Improperly installed filter or leaking filter connection– May need to replace sealant if this is the case.

Insufficient chlorine in the pool water due to excess bather load or poor water management.

Over-chlorination-Resulting in high levels of free chlorine

Free Chlorine readings -Come back at low levels but then increase with bather loads and changing weather patterns.

Voids in the chlorine system – You can cause this by cracks or leaks in your piping, walls, or skimmers. Please get in touch with your local pool professional for repair and inspection if this is the case.

Slow the flow of water into the pool-Water temperature too cold for chlorine to dissolve (chlorine tablets will completely dissolve at a temperature of 68-77 degrees Fahrenheit).

Too much hay or grass in the pool (this can absorb chlorine).


Hot tub sponges are essential items in the backyard Spa. They help clean the water and make it fresh, clear, and odor-free.

Choosing a suitable hot tub sponge can be tricky, so I hope this article has helped you better understand its different types and how they work.


Hi! I' am Tom. I was a manager in one of the biggest stores for over 10 Years, am also an SEO by night. I don't like to call myself a blogger; they are very analytical, do email marketing, and know all SEO stuff. I faced many questions from customers about different products, and there was hardly any help on the internet. After learning all the things about these products as a manager the hard way, I decided to start a blog and help other people.

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