Remove Iron from Hot Tub Water: A Guide to a Spotless Soak

Iron in hot tub water can cause staining, discoloration, and can even affect the performance of your hot tub. Here are some ways to remove iron from hot tub water:

  1. Use a metal sequestrant: A metal sequestrant is a chemical that helps to bind and remove iron and other metal ions from your hot tub water. Simply add the sequestrant to your hot tub and allow it to circulate for a few hours.
  2. Install an iron filter: An iron filter is designed specifically to remove iron from hot tub water. Install the filter in line with your hot tub’s plumbing and allow the water to circulate through it.
  3. Use an oxidation process: An oxidation process uses chlorine or hydrogen peroxide to break down iron and other contaminants in your hot tub water. Simply add the appropriate oxidizing agent to your hot tub and allow it to circulate for a few hours.
  4. Drain and refill the hot tub: If you have a high level of iron in your hot tub water, you may need to drain and refill the hot tub to completely remove the iron. Make sure to properly sanitize the hot tub before refilling it with clean water.

By following these steps, you’ll be able to effectively remove iron from your hot tub water, ensuring a spotless soak every time.

Can I get Iron out in my Hot Tub?

Fortunately, you can always remove the stains from the iron. There are plenty of iron metal removers. You only need to find the best one that excellently removes the stains due to the iron deposits.

Spa Choice is one of the best products for removing iron stains from a hot tub. First, it has a downloadable guide that makes its use a total breeze. The instructions are straightforward to help you excellently remove stains and prevent future iron stain formation. What’s more, you get a pack of two stain removers if you opt for Spa Choice! That is enough to handle stain removal of any size.

SpaChoice 472-3-1001-02 Metal Gone for Spa Hot Tub, 1-Pint, 2-Pack
  • Helps prevent metal staining and corrosion
  • Use this product when filling or refilling your spa
  • Add 16 ounces of this product around the spa waterline for each 625 gallons of spa water

How do you Remove Iron Stains from a Hot Tub?

Hot tubs are great. They help you relax as soon as you step inside them. But iron stains under their faucets might create an ugly scene that only frustrates your soaking experience. You can always get rid of the iron stains on your hot tub for an elegant look.

Although you can find many products on the market, only a few work as excellently as In The Swim Spa metal remover. Besides removing the iron stains, this product also eliminates chelated copper. It contains Hydroxyethylidene Diphosphonic Acid that dissolves and removes any iron stain on a hot tub.

In The Swim Spa and Hot Tub Metal Out - 1 Quart
  • Suggest for use with well water
  • Chelates copper and iron
  • Safe in all spa/hot tub interior types
  • Active Ingredient: Hydroxyethylidene Diphosphonic Acid (HEDP) 5 - 6%
  • Dosage: 16 ounces per 500 gallons

The bottle has only a quart of the stain remover, but it is still ideal for removing stains on a 500-gallon hot tub. Be sure to use 16 ounces of the remover on a 500-gallon hot tub for an excellent cleaning result.

What is the Brown Stuff in my Hot Tub?

The brown stuff in your hot tub might be scum. When looking to remove scum, you should know its cause. Besides the brown scum, your hot tub may also have green and blue-green scum. 

Each of these scum types has its cause, and battling the scum means getting the right remover. But you will only choose a suitable remover after knowing the cause of the scum. Brown scum will form when the water’s pH level is too high. And this causes iron in the water to react with the chlorine. 

The reaction will create a nasty brown scum that will float at the water’s surface. The scum may also stick on the walls of your hot tub. And that’s what the brown stuff on your hot tub is all about.

How do you Get Stains out of a Hot Tub?

A stain remover comes in handy when looking to remove nasty stains that reduce the glimmer of your hot tub. Most stain removers need a soft rag for wiping off the stains. So, be sure to choose a soft rag. An abrasive rag will only scratch your hot tub’s smooth glimmering surface, which may damage the glossy finish.

Your starting point will be switching off the power supply to the hot spa. Then draining the water becomes the next step. You can then wipe off the stained parts to restore the glossy finish for a brand-new look!

But wiping off the stains is useless if you don’t take measures to prevent stain formation again. Be sure to maintain proper water chemistry to avert scum formation on the hot tub. Make sure the pH level of the hot tub water is balanced after adding sanitizers and other chemicals.

How do I Get Rid of Brown Stains in my Hot Tub?

Higher pH levels in your bath water may cause brown scum on the hot tub. Once you have understood this concept, it becomes easier to pick out the best scum remover. Products such as SpaGuard Spa Stain remover work efficiently to remove brown stains in hot tubs.

SpaGuard Spa Stain/Scale Control - Quart
  • SpaGuard Spa Stain & Scale Control - 1 Quart
  • Prevents scale formation and cloudy water due to high calcium levels
  • Removes some scale buildup on spa surface
  • Removes relatively fresh metal stains from spa surfaces
  • Simply add this powerful liquid formula weekly to safeguard your spa or hot tub from these threats.Color of the liquid is natural brown

Once your hot tub has its original high-gloss finish that glimmers, you could use Impresa sponges to prevent scum formation. You can also use a pH decreaser to avoid the appearance of brown scum on the hot tub’s walls.

IMPRESA 3-Pack Scum Star Oil Absorbing Sponge - Excellent Absorber for Hot Tub, Spa and Swimming Pool Use - Compare to The Bugs and Balls - Made in USA
  • Soaks Up All The Gunk: Absorbs 40x+ its weight in inanimate scum, suntan lotion, body oils, make-up/cosmetics, pollen, etc. without absorbing any water. Our oil absorber sponge helps eliminate the inanimate scumline that forms in swimming pools, hot tubs, jetted tubs, jacuzzies and spas
  • The Original Scum Star With Lots Of Surface Area: The unique star shape provides plenty of surface area for maximum efficiency and ensures that it won't get stuck in your water lines
  • Useful Cleaner: Place one in your pool skimmer and let two float around freely (flip occasionally). A great alternative to the bug / bugs and ball / balls.
  • Improves The Efficiency Of Your Filtration System: By absorbing inanimate scum and lotions / oils, the Scum Stars help lighten the load on your filtration system and filter, maximizing their life span and minimizing maintenance costs. Soaks up so many things you don't want in your water, making it one of the perfect hot tub accessories
  • Made In The USA: Three pack of sponges (as shown). Each unit will last approximately one swimming season. Highly effective at an excellent value. Proudly Made In The USA!

Be sure to check out SpaGuard pH Decreaser if you’re looking to prevent future brown scum formation. The product might yield the results you’ve been looking for, so it’s worth checking out the product.

SpaGuard pH Decreaser - 22 oz
  • Protects spa and equipment due to improper pH
  • Prevents cloudy water due to high pH
  • Balances water for bather comfort

Can Well Water Stain my Spa?

Yes, water from a well might stain your spa. Iron is one of the metals in well water. When it reacts with chlorine, it creates a brown scum that will spoil the walls of your hot spa. Iron also increases the water’s pH value, thus causing your hot spa to have stains.

You can always use a product that balances the water’s pH value to prevent stain formation on your hot spa. But on the positive side, well water is natural and has no additives. Therefore, it is safer than your household water supply.

Be sure to check out the Hot Tub Things pH balancer if you are looking to prevent stain formation on your hot tub. The product keeps your hot tub water in check by ensuring the acidity and alkalinity levels balance out.

You can also look for other incredible pH balancers to maintain your hot tub’s excellent gloss finish.

Hot Tub Things pH Up and Alkalinity Up - Balancing Formula, Spa Care with pH Plus & Alkalinity Increaser, Maintain Pool, Hot Tub, and Spa Crystal Clear Water Quality, Relaxation - 2 Pounds
  • Optimal Water Balance: Achieve the perfect pH and alkalinity levels effortlessly. Maintain ideal chemical balance for a soothing, clean spa experience. This potent formula ensures your water chemistry stays within recommended ranges for enhanced relaxation and performance.
  • Comprehensive Compatibility: Works seamlessly with various purification systems like chlorine, bromine, and mineral purifiers. Suitable for freshwater pools of different sizes, catering to pools up to 2000 gallons and ensuring consistent, balanced water quality.
  • Effortless Application: Simplify maintenance routines. Easily administer the product directly into your hot tub or pool. Just add it as needed during your routine pH and alkalinity checks. Keep your water in optimal condition without hassle or complexity.
  • Professional Instructions for Use: Clear, step-by-step guidance ensures you get it right every time. Detailed usage instructions provided to efficiently raise pH levels and alkalinity. Test, add, circulate, and retest—achieving perfect balance is straightforward.
  • Trusted Expertise: Hot Tub Things brings over 30 years of industry expertise. We're dedicated to delivering top-notch spa parts, exceptional service, and unbeatable prices. Trust in our commitment to quality for your ultimate spa experience.

Is Well Water Hard to Balance in Spas?

While well water is naturally pure and has no chemicals added to it, you can be sure to find plenty of iron and other metal deposits in the water. Dirt may also be lurking in the water. All these impurities can stain the high-gloss surface of your hot spa.

The impurities also make it very challenging to balance the pH level of your hot tub’s water. Yes, well water has high iron content and is very difficult to balance. But with proper balancers, you can excellently balance the pH of your bathwater. And this will prevent the formation of brown scum on the surfaces of the hot spa.

Is it OK to fill a hot tub with well water?

It is absolutely okay to fill your hot spa with well water. But you need to understand a few things. First, well water has iron metal and other minerals such as calcium and magnesium. As such, it is considered “hard.”

There might also be dirt and other impurities, which are not dangerous but definitely annoying. With excellent filtration, your well water will be free of dirt and other contaminants. As a result, your hot spa will be relaxing since the water will not only have the desired temperature but will be clear as well.

Pre-Filtering Well Water While Filling a Hot Tub

When looking to fill your hot tub with well water, be sure to filter the well water. And there are a few ways of doing so. First, connect the well water to your home’s water treatment system before channeling it to a hot tub.

Second, you can use a pre-filter. You can find plenty of pre-filters online on e-commerce platforms. For hot tub owners who like to get their hands-on tools, DIY bucket fillers are an excellent choice!

Pre-filtering the well water ensures dirt and other impurities don’t make it to the hot tub. And this reduces the chance of stain formation on the surfaces of the hot spa. Therefore, it is essential to filter the well water before filling your hot tub with it.

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Emily Williams

Emily is a passionate Hot Tubs researcher who loves writing about all things Hot Tubs! She has years of experience and a knack for simplifying complex concepts, these articles are here to answer all your burning questions in a simple and easy to read style.
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