Considering a saltwater hot tub? Pros and cons

Saltwater in a hot tub? When it comes to hot tubs, the traditional method of keeping the water clean and clear has been through the use of harsh chemicals like chlorine. However, in recent years, an alternative method has gained popularity: saltwater hot tubs.

 

By using a saltwater system, hot tub owners can enjoy a more natural and gentler approach to water treatment. But is a saltwater hot tub the right choice for you?

 

In this blog post, I’ll explore the pros and cons of saltwater hot tubs, so you can make an informed decision about whether this innovative system is the best fit for your lifestyle and preferences. So, whether you’re a seasoned hot tub owner or considering your first dip, read on to learn more about the benefits and drawbacks of a saltwater hot tub.

 

What is a Salt Water Hot Tub?

A saltwater hot tub, also known as a chlorine generator hot tub or a mineral spa, is a type of hot tub that uses a salt chlorine generator to sanitize the water instead of traditional chlorine or bromine. The salt chlorine generator converts salt (sodium chloride) into chlorine (sodium hypochlorite) through a process called electrolysis. This chlorine then sanitizes the water, killing bacteria and other microorganisms.

Saltwater hot tubs offer several advantages over traditional hot tubs:

• Softer, gentler water: The chlorine produced by a salt chlorine generator is less harsh than traditional chlorine, making the water softer and more gentle on the skin and eyes.

• Reduced chemical odor: Saltwater hot tubs do not have the strong chlorine smell that is often associated with traditional hot tubs.

• Reduced chemical usage: Saltwater hot tubs require less chlorine than traditional hot tubs, which is better for the environment and can save money in the long run.

• Increased buoyancy: The salt in the water adds buoyancy, making it easier to float.

• Easier maintenance: Saltwater hot tubs are generally easier to maintain than traditional hot tubs because the salt chlorine generator does most of the work for you.

However, there are also a few potential drawbacks to saltwater hot tubs:

• Higher initial cost: Saltwater hot tubs typically cost more than traditional hot tubs upfront.

• Increased corrosion: Saltwater can be corrosive to some metals, so saltwater hot tubs may require more maintenance than traditional hot tubs in the long run.

• Potential for algae growth: Saltwater hot tubs are more susceptible to algae growth than traditional hot tubs.

Overall, saltwater hot tubs are a good option for people who are looking for a more natural and environmentally friendly way to sanitize their hot tub water. They are also a good choice for people who are sensitive to chlorine or who have skin or eye irritation. However, saltwater hot tubs are more expensive than traditional hot tubs, and they may require more maintenance in the long run.

Here is a table summarizing the pros and cons of saltwater hot tubs:

How Does a Salt Water Hot Tub Work?

A saltwater hot tub, also known as a chlorine generator hot tub or a mineral spa, utilizes a salt chlorine generator to sanitize the water. This method differs from traditional hot tubs that rely on chlorine or bromine for sanitation.

The core of a saltwater hot tub’s operation lies in a process called electrolysis. This involves passing an electric current through salt (sodium chloride) dissolved in the hot tub water. During this process, the sodium chloride molecules split into sodium (Na+) and chloride (Cl-) ions. The chloride ions then react with each other and with water molecules to form hypochlorous acid (HOCl), which is a potent sanitizer.

The generated hypochlorous acid effectively kills bacteria, viruses, and other microorganisms, ensuring the cleanliness of the hot tub water. The level of chlorine production is regulated by the salt chlorine generator, maintaining a consistent sanitizing effect without the harshness of traditional chlorine.

Here’s a simplified breakdown of the electrolysis process in a saltwater hot tub:

1. Salt (NaCl) dissolves in the hot tub water.

2. An electric current is passed through the salt solution.

3. The salt molecules dissociate into Na+ and Cl- ions.

4. Cl- ions react with each other and with water molecules to form HOCl (hypochlorous acid).

5. HOCl acts as a sanitizer, killing bacteria, viruses, and other microorganisms.

6. The salt chlorine generator monitors and controls the level of HOCl in the water.

7. The sanitized water circulates through the hot tub jets, providing a relaxing and clean soaking experience.

What is the difference between Chlorine from a Salt System and Chlorine in a Bottle?

The main difference between chlorine from a salt system and chlorine in a bottle is how the chlorine is produced.

Chlorine from a salt system is produced through electrolysis, a process that passes an electric current through saltwater to create hypochlorous acid (HOCl), which is a form of chlorine. This process is more natural and environmentally friendly than the production of bottled chlorine, which is often made from bleach.

Bottled chlorine is typically made from sodium hypochlorite (NaClO), which is a harsher form of chlorine than HOCl. This is because NaClO contains cyanuric acid (CYA), which is a stabilizer that helps to prevent chlorine from breaking down in sunlight. However, CYA can also build up in the water over time, making it more difficult for the chlorine to sanitize the water and potentially leading to skin and eye irritation.

In addition to being more natural and environmentally friendly, chlorine from a salt system is also less harsh on the skin and eyes than bottled chlorine. This is because HOCl is a more stable form of chlorine and does not contain CYA.

Here is a table summarizing the key differences between chlorine from a salt system and chlorine in a bottle:

Why does bottled Chlorine have added Chemicals?

Bottled chlorine has added chemicals for several reasons:

• Stability: Chlorine is a reactive molecule that can break down in sunlight. Cyanuric acid (CYA) is added to bottled chlorine to stabilize it and prevent it from breaking down too quickly. This helps to ensure that the chlorine will continue to sanitize the water for longer periods of time.

• pH adjustment: Chlorine is most effective when the water has a pH between 7.2 and 7.8. Sodium hydroxide (NaOH) is often added to bottled chlorine to raise the pH of the water and make it more effective.

• Prevention of algae growth: Algae is a common problem in pools and spas, and it can be difficult to control. Algaecides are often added to bottled chlorine to prevent algae growth.

• Prevention of corrosion: Chlorine can be corrosive to metals, such as stainless steel and aluminum. Sodium silicate (Na2SiO3) is often added to bottled chlorine to prevent corrosion.

• Odor control: Chlorine has a strong odor that can be unpleasant to some people. Fragrance is often added to bottled chlorine to mask the odor.

While these added chemicals can be helpful in some ways, they can also have some drawbacks. For example, CYA can build up in the water over time and make it more difficult for the chlorine to sanitize the water. Algaecides can also be harmful to some aquatic animals. Sodium hydroxide can raise the pH of the water too high, making it difficult to control. Sodium silicate can leave a residue on pool surfaces that can be difficult to remove. And fragrance can be irritating to some people’s skin and eyes.

In general, it is best to use bottled chlorine as directed and to avoid using it more often than necessary. If you are concerned about the added chemicals in bottled chlorine, you can use a salt chlorine generator instead. Salt chlorine generators use electrolysis to produce chlorine from salt, and they do not require any added chemicals.

Here is a table summarizing the reasons why bottled chlorine has added chemicals:

Will I save money on Chemicals with a salt system?

Whether or not you will save money on chemicals with a salt system depends on a number of factors, including the size of your pool, the frequency of your pool use, and the cost of chemicals in your area.

Initial Cost

Salt systems typically have a higher initial cost than traditional chlorine systems. This is because they require a salt chlorine generator, which is an additional piece of equipment. The cost of a salt chlorine generator will vary depending on the size of your pool and the brand of the generator.

Ongoing Cost

Once you have installed a salt system, the ongoing cost of chemicals will be lower than with a traditional chlorine system. This is because you will only need to purchase salt to generate chlorine, and salt is much cheaper than chlorine tablets or liquid chlorine.

Estimated Savings

According to the Pool and Hot Tub Alliance, you can save up to 50% on chemicals by using a salt system. However, your actual savings will vary depending on the factors mentioned above.

Factors Affecting Savings

• Pool size: The larger your pool, the more money you will save with a salt system. This is because you will need to purchase more chlorine tablets or liquid chlorine for a larger pool.

• Frequency of pool use: The more frequently you use your pool, the more money you will save with a salt system. This is because you will need to replenish your chlorine supply more often for a pool that is used frequently.

• Cost of chemicals: The cost of chemicals will vary depending on your location. If you live in an area where chemicals are expensive, you will save more money with a salt system.

Conclusion

If you are looking for a way to save money on pool chemicals, a salt system is a good option. However, it is important to factor in the initial cost of the system before making a decision.

Here is a table summarizing the potential cost savings of using a salt system:

6 Key Facts 

 

Here are six important things to know about owning a saltwater hot tub:

 

1. Saltwater hot tubs still require maintenance – While saltwater systems use natural chlorine generated from salt, they still require regular maintenance to keep the water clean and balanced. This includes testing the water chemistry, cleaning the filter, and occasionally adding chemicals to adjust the pH or alkalinity levels.
2. Saltwater systems can be more expensive upfront – While saltwater hot tubs can save you money on chemical costs in the long run, the initial cost of installation can be higher than a traditional hot tub. This is because a saltwater system requires specialized equipment.
3. Saltwater hot tubs can be gentler on the skin – For people with sensitive skin, a saltwater hot tub may be a better choice than a traditional hot tub with harsh chlorine chemicals. Saltwater is gentler on the skin and can leave it feeling softer and less irritated.
4. Saltwater systems can be more eco-friendly – Unlike traditional hot tubs, saltwater systems do not require the use of harsh chemicals that can harm the environment. In addition, saltwater systems use less energy than traditional hot tubs because they do not require as much power to run the system.
5. Saltwater hot tubs require a lower level of salinity – Saltwater hot tubs require a higher level of salinity than the ocean, typically around 3000 to 5000 parts per million (ppm). This means that adding too much salt can be harmful to the system and may require draining and refilling the hot tub.
6. Saltwater hot tubs may require more maintenance for the hot tub cover – Saltwater systems can be corrosive to some hot tub cover materials, such as metal or cheap vinyl. It is important to choose a hot tub cover that is specifically designed to withstand saltwater conditions.

 

What are the Myths of Salt Water in a Hot Tub?

 

When it comes to saltwater systems for hot tubs, there are several myths and misconceptions that have circulated among hot tub owners. Let’s debunk some of these common myths:

Myth 1: Saltwater hot tubs are completely chlorine-free. Fact: Saltwater hot tubs do utilize salt to produce chlorine, but they are not entirely chlorine-free. Saltwater systems use a process called electrolysis, where salt is converted into chlorine through a salt cell. This chlorine is then used to sanitize the water. While the chlorine levels may be lower compared to traditional chlorine-based systems, it is still present in the water.

Myth 2: Saltwater hot tubs are maintenance-free. Fact: While saltwater systems can simplify the maintenance process to some extent, they are not entirely maintenance-free. Regular water testing, pH adjustments, and occasional cleaning of the salt cell are still necessary to maintain proper water balance and sanitation. Additionally, the water chemistry should be monitored and adjusted as needed.

Myth 3: Saltwater hot tubs won’t damage or corrode the equipment. Fact: Saltwater can be corrosive to certain materials, including metal components and some types of hot tub equipment. It’s important to choose a hot tub model and equipment that are specifically designed to handle saltwater environments. Regular inspections and maintenance of the equipment are essential to prevent corrosion and ensure longevity.

Myth 4: Saltwater hot tubs won’t irritate the skin or eyes. Fact: Saltwater systems, just like chlorine-based systems, can potentially cause skin and eye irritation if not properly balanced. Improper water chemistry, such as high chlorine levels or unbalanced pH, can lead to discomfort. Regular water testing and maintaining appropriate water balance are key to minimizing potential irritations.

Myth 5: Saltwater hot tubs are more expensive to maintain. Fact: While the initial investment for a saltwater system may be higher than a traditional chlorine system, the long-term maintenance costs can be comparable or even lower. Salt cells typically last for a few years before requiring replacement, and the ongoing cost of salt is generally lower compared to purchasing chlorine products regularly.

It’s important to note that the effectiveness and experience of a saltwater hot tub can vary depending on factors such as the quality of the system, proper installation, and maintenance practices. If you’re considering a saltwater hot tub, it’s recommended to consult with a reputable dealer or manufacturer to understand the specific requirements and benefits of the system for your hot tub.

Remember, regardless of the sanitization method you choose, proper water maintenance and regular testing are crucial for maintaining a clean and safe hot tub environment.

 

What are the Benefits of Mineral Filtration in a Hot Tub?

 

Mineral filtration is becoming an increasingly popular method of water treatment in hot tubs, and for good reason. One of the main benefits of mineral filtration is that it can reduce the amount of harsh chemicals needed to keep the water clean and balanced.

 

This is because mineral filtration systems use natural minerals, such as copper and silver, to help sanitize the water. These minerals work together to destroy bacteria, algae, and other contaminants, leaving the water clean and clear. In addition, mineral filtration can also help to soften the water and make it feel smoother on the skin.

 

This can be especially beneficial for people with sensitive skin or those who experience dryness or irritation from traditional hot tub chemicals. Overall, mineral filtration can provide a more natural and gentle approach to water treatment in hot tubs, while still maintaining a clean and healthy environment for you to enjoy.

 

How do Salt Water Systems Work in a Hot Tub?

 

Saltwater systems in hot tubs work by generating natural chlorine from salt. The system consists of a salt cell, which is a chamber that contains a series of metal plates coated with a thin layer of specialized material.

 

When an electric current is passed through the cell, the salt in the water is converted into hypochlorous acid, which is a natural form of chlorine. This process, known as electrolysis, releases the chlorine into the water, where it acts as a sanitizer to kill bacteria and other contaminants.

 

The level of salt in a saltwater hot tub is typically around 3,000 to 5,000 parts per million (ppm), which is much lower than the salt level in seawater. The salt is added to the hot tub as needed and does not need to be replenished very often, as it does not evaporate with the water.

 

One of the benefits of using a saltwater system in a hot tub is that it can provide a more natural and gentle approach to water treatment, without the harsh chemicals that are often used in traditional chlorine-based systems. Saltwater systems can also help to reduce the amount of maintenance required for the hot tub, as they can be more efficient and require less frequent chemical additions.

 

However, it is important to note that saltwater systems still require regular maintenance to ensure that the water remains balanced and clear. This includes testing the water chemistry regularly, cleaning the filter, and occasionally adding chemicals to adjust the pH or alkalinity levels.

 

Overall, saltwater systems can be a great option for hot tub owners who want a more natural and gentle approach to water treatment, but it is important to understand how they work and the maintenance required to keep the system running effectively.

Can I have a salt water inflatable hot tub?

Inflatable hot tubs are generally designed for use with traditional chlorine or bromine-based chemical sanitizers rather than salt water systems. This is because inflatable hot tubs typically have materials and components that may not be compatible with the corrosive effects of saltwater. Saltwater contains salt, which can be harsh on certain materials over time.

If you want a saltwater system for your hot tub, it’s advisable to consider a more permanent or rigid hot tub made for saltwater use. These are typically constructed with materials and components that can withstand the saline environment. Saltwater hot tubs have a salt cell that converts the salt into chlorine through a process called electrolysis, providing a more natural and gentler way to sanitize the water.

However, it’s important to note that converting an inflatable hot tub into a saltwater system would likely involve significant modifications, and it might not be practical or cost-effective. Additionally, any such modifications could void the warranty on the inflatable hot tub.

If you’re specifically interested in the benefits of a saltwater system, it’s recommended to consider a traditional hot tub that is designed and equipped for saltwater use. These systems offer the advantages of reduced chemical use and softer, more natural-feeling water, which many people find enjoyable. Be sure to follow the manufacturer’s guidelines for maintenance and water chemistry to ensure the longevity and performance of your hot tub.

How much does a salt water hot tub cost?

The cost of a saltwater system for a hot tub primarily depends on the type and quality of the saltwater generator, also known as a salt chlorinator or salt cell. The price can vary based on the brand, model, and features of the generator. Here’s a general price range for saltwater generators:

1. Basic Models: Entry-level saltwater generators may cost between $300 to $700. These models provide the basic functionality of converting salt into chlorine for hot tub sanitation.

2. Mid-Range Models: Mid-range salt cells typically range from $700 to $1,200. They often come with additional features such as self-cleaning functions, digital displays, and more precise control over chlorine production.

3. High-End Models: High-end or premium saltwater generators can cost $1,200 or more. These units often offer advanced technology, longer lifespan, and enhanced performance.

In addition to the initial cost of the salt cell, you should also consider the following factors:

• Installation: If you’re not installing the salt cell yourself, you may need to hire a professional, which can add to the installation cost.

• Maintenance: While saltwater systems typically require less maintenance than traditional chemical-based systems, you’ll still need to periodically test the water, clean the cell, and replace it when it reaches the end of its lifespan (usually every 3-7 years, depending on the model).

• Salt: You’ll need to purchase pool-grade salt to maintain the appropriate salt level in the water. The cost of salt can vary depending on your location and the quantity needed.

• Energy Costs: The operation of the salt cell does consume electricity, so there will be some ongoing energy costs.

It’s important to choose a salt cell that is appropriately sized for the volume of water in your hot tub. You should also consult with the manufacturer or a professional hot tub technician to ensure you select a saltwater generator that is compatible with your specific hot tub model.

Keep in mind that while a saltwater system may have higher upfront costs than traditional chemical-based systems, it can offer long-term savings and the benefit of softer, more natural-feeling water. Additionally, saltwater systems are generally considered more environmentally friendly.

Can I add a Salt Water system to my hot tub?

Yes, you can certainly add a saltwater system to your hot tub. These systems, often referred to as salt chlorinators or salt cells, are a popular choice for hot tub owners looking for a more natural and convenient way to maintain water quality.

When installing a saltwater system in your hot tub, it’s important to position the salt cell after the filter and just before the water is returned to the hot tub via the jets. This placement allows for efficient water filtration and treatment. Here’s why this order of equipment is recommended:

1. Filtration: Placing the filter before the salt cell ensures that the water is adequately filtered before it enters the salt cell. This helps remove impurities and debris, resulting in cleaner water that the salt cell can then effectively treat.

2. Chemical Treatment: The salt cell generates chlorine through a process called electrolysis. By positioning the salt cell after the filter, you’re essentially treating clean, filtered water with chlorine, resulting in more efficient and effective water sanitation.

3. Circulation: The water circulation system in most hot tubs is designed to draw water through the filter first and then return it to the hot tub via the jets. Placing the salt cell in this flow path ensures that the chlorinated water is evenly distributed throughout the hot tub.

This order of equipment installation not only maximizes the effectiveness of the saltwater system but also helps ensure that the water is safe and enjoyable for hot tub users.

It’s important to follow the manufacturer’s guidelines and recommendations for installing the salt cell in your specific hot tub model. If you’re unsure about the installation process, get in touch and I can supply some guidance and assistance.

How to increase free chlorine in salt water hot tub?

Saltwater hot tubs can have a lower environmental impact than some other types, but it’s important to consider all aspects:

Positives:

• Reduced chemical use: Compared to traditional chlorine or bromine systems, saltwater generators produce their own sanitizer via electrolysis, minimizing the need for additional chemicals. This reduces potential harm to aquatic life and groundwater if disposed of improperly.
• Less chlorine smell: Saltwater systems often generate lower levels of free chlorine, leading to a milder smell and potentially less irritation for sensitive users.
• Energy efficiency: Some saltwater systems claim to be more energy-efficient than older chlorinator models,although this heavily depends on specific technology and usage patterns.

Negatives:

• Salt usage: Saltwater systems still require periodic addition of salt, which can be extracted through energy-intensive processes and potentially contaminate marine environments if disposed of incorrectly.
• Electrolysis equipment: The salt cell and generator require electricity to function, potentially negating some of the energy savings if the grid relies on heavily polluting sources.
• Chlorine production regardless: While reduced compared to traditional methods, saltwater systems still create chlorine through electrolysis, contributing to its presence in the environment.
• Disposal of spent cells: Salt cells eventually wear out and need replacement. Disposing of them responsibly is crucial to avoid environmental damage.

Comparison to other options:

• Chlorine/Bromine: Typically require more chemical additions, potentially leading to higher environmental impact. However, they can be cheaper overall and often work well in low-usage scenarios.
• Ozone: Considered the most eco-friendly option as it doesn’t use harmful chemicals, but requires additional equipment and may not be effective alone for heavy bather loads.
• Mineral systems: Less common but gaining traction, these use natural minerals like silver and copper to purify water, reducing chemical reliance but needing frequent filter changes and possibly supplemental sanitation methods.

Overall:

Saltwater hot tubs can be a decent eco-friendly choice, but their impact depends on various factors like specific technology, energy source, usage patterns, and responsible disposal practices. Consider evaluating all options based on your needs and environmental priorities.

Additionally:

• Energy efficiency matters: Regardless of sanitizer type, choosing an energy-efficient hot tub model with good insulation and smart control features can significantly reduce your overall environmental footprint.
• Minimize water usage: Practice responsible water management by draining and refilling only when necessary and consider using covers to minimize evaporation.
• Maintain responsibly: Proper maintenance ensures efficient equipment operation and reduces the need for excessive chemical adjustments, contributing to a greener hot tub experience.

What is an Alternative to Salt Water in a Hot Tub?

 

Ultraviolet (UV) water treatment systems can be an effective alternative to saltwater systems in hot tubs. UV systems use a lamp that emits a specific wavelength of light that is able to destroy bacteria, viruses, and other contaminants in the water. This process, known as UV-C radiation, works by disrupting the DNA of microorganisms, which renders them unable to reproduce and spread.

 

One of the main benefits of UV systems is that they do not require the use of chemicals or salts, which can be harsh on the skin and the environment. This can make them a more natural and eco-friendly option for hot tub owners.

 

Additionally, UV systems can help to reduce the amount of maintenance required for the hot tub, as they do not require the same level of monitoring and adjustment as traditional chlorine-based systems.

 

However, it is important to note that UV systems alone may not be enough to keep the water completely sanitized, and may need to be used in combination with other treatment methods, such as active oxygen, chlorine or bromine although in reduced quantities.

 

Additionally, UV lamps need to be replaced periodically, typically every 1-2 years, to ensure that they are working effectively.

 

Overall, UV water treatment systems can be a great alternative to saltwater systems in hot tubs, providing a more natural and eco-friendly approach to water treatment while still maintaining a clean and healthy environment for you to enjoy.

Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi

 

Hi, Andi here. I own Buildahottub.com and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Today, I've helped over 1000 DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi