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Hot Tub Ionizer Introduction

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ClearBlue Mineral System

What is a Mineral System?

Hot Tub Ionizer: What is it and what does it do?

If you are in the market for a hot tub or have one at home, you may have encountered the fabled hot tub ionizer. So, what exactly is a hot tub ionizer? What does a hot tub ionizer do, and where can you get one?

Hot tub ionizer is a natural mineral sanitizer

A hot tub ionizer is a natural sanitizer for the water. A mineral cell is plumbed into the hot tub filtration system using a tee. The cell plugs into an electrical controller powered by either the spa pack or a standard household power outlet. There are settings on the controller that regulate the release of minerals (silver, copper, and zinc) into the water. These minerals have anti-microbial properties, so you can reduce the chlorine and other chemicals needed to sanitize the water.

ClearBlue Mineral System Package
ClearBlue Mineral System for Hot Tubs

What does an ionizer do in a hot tub?

An ionizer uses a combination of minerals to disinfect the water from bacteria, viruses, protozoa, and other microscopic organisms. Without this action in the water, you can get rashes, irritated skin, and even feverish and sick. Minerals are released electrically from a set of electrodes plugged into a controller. Charged microscopic ions are released into the water, where they are attracted to microorganisms. The ions penetrate the cell walls of the organisms and disrupt the cellular process, which causes the cells to die. The dead cells clump together with the mineral ions and are removed from the water by the filter.

Hot tub ionizer benefits

A hot tub ionizer’s primary benefit is reducing the chlorine, bromine, or other harsh chemical typically used as a sanitizer. While you still need some, you can reduce it to as low as 0.5 ppm from the standard recommendation of 3 ppm – 5 ppm. That’s up to 90%!

Additional hot tub ionizer benefits

  • Natural: Hot tub ionizers use elemental minerals as a disinfectant. There are no artificial additives or chemicals. This makes the water easier on the skin and extends the life of the hot tub equipment.
  • Easy: Hot tub ionizers use a controller for dosing the minerals. The process is automated so you don’t need to make adjustments often or add anything.
  • Low Maintenance: The mineral cell that releases minerals lasts several years in a hot tub. In contrast, mineral cartridges need to be changed every 6 months.
  • Low Power: Ionization is a low-power process. Whereas salt systems and UV systems require a higher current to operate, ionization is a low current. This helps save money on your power bill.
  • Inexpensive: Hot tub ionizers lower the overall cost of owning and maintaining a hot tub. While you have to pay the price upfront to install it, you save money on chemicals, so it pays for itself. You also get more life from your hot tub and equipment.
  • Proven: Ionizers have been used in various water treatment applications for over 30 years.

Hot tub ionizers and pH

Since the minerals are pH neutral, the water pH stays balanced longer. This is important because a 1.0 change in pH reduces the sanitizing efficiency by 40%. This means you would need more than twice as much chlorine to do the same job!

The pH is the primary factor in how comfortable the water is on your skin, both during and after hot tub use. The closer the pH stays to the neutral reading of 7.2, the better the water is for your skin.

Hot tub ionizers ease the pain of constantly balancing pH.

What are the downsides of hot tub ionizers?

The biggest downside of hot tub ionizers is that they are not a complete sanitizing solution. You still need to maintain a low chlorine or bromine level to oxidize organics. Mineral ions assist in controlling bacteria, algae, and other microorganisms, but the kill rate is slower than chlorine and bromine, so health officials recommend having some chlorine or bromine in the water as well.

The other inconvenience with hot tub ionizers is that the levels must be checked regularly using a copper test. If the levels are too low, they need to be boosted, which means you have to change the settings on the controller. If the levels are too high, they can collect at the waterline, leading to stains.

How are hot tub ionizers different from mineral cartridges?

Hot tub ionizers and mineral cartridges are similar because they use mineral ions to help sanitize the water. Whereas mineral cartridges use a chemical compound that is released into the water by dissolving, hot tub ionizers use an electrical ionization process. So, while mineral cartridges have added ingredients to assist in the release process, ionizers use pure, elemental minerals. These added ingredients are often toxic at high levels, so kids and pets mustn’t get into them.

Mineral cartridges cannot regulate the mineral output and rely on water flow. This means the levels will vary depending on the hot tub size and pump usage. Hot tub ionizers give you complete control over the levels and allow you to test them to ensure it’s working and optimized.

Mineral cartridges must be changed every 6 months, and the effectiveness slowly tapers. Hot tub ionizers are consistent throughout the lifespan of the mineral cell and only need to be changed every 2-3 years.

Mineral cartridges can only be used if your hot tub has a spot built-in to put them. Ionizers can be fitted to most hot tubs, although it’s a bit of a process.

Hot tub ionizers vs ozonators

Hot tub ionizers and ozonators are both ‘alternative sanitizers’ that allow you to reduce the chlorine and other chemicals required to sanitize the water. Whereas ionizers use a residual of mineral ions in the water, ozonators use ozone gas that bubbles through the water to oxidize organics and contaminants in the water.

Since hot tub ionizers and ozonators have complementary benefits and delivery mechanisms, using them both is worthwhile. The mineral ion residual always works because it’s very stable in the water. Ions can sanitize the water in the pipes, filter, and all the nooks and crannies of the hot tub. Ozone effectively breaks down bather waste like lotions, makeup, and sunscreen. So, the two work well together.

More on hot tub ionizers vs ozonators here.

Hot tub ionizers vs UV

Hot tub ionizers and UV are both ‘alternative sanitizers’ that allow you to reduce the chlorine requirement. Whereas ionizers use residual mineral ions that build up in the water, UV systems sanitize the water as it passes through the UV chamber. Hot tub ionizers that use silver have similar anti-microbial benefits as UV, so they overlap. Whereas hot tub ionizers and ozone are complementary, you won’t see much benefit from combining ionizers with UV.

Whereas hot tub ionizers use a mineral cell to release minerals, UV systems use a light bulb. With hot tub ionizers, it’s easy to see how much life is left because you can see the electrodes and gauge how much material is left. UV systems make it hard to know how much life is left on the bulb.

Whereas hot tub ionizers use minerals you can test for, UV has no testing method. Therefore, it’s difficult to know if UV systems are working unless you open your hot tub panel and inspect the system.

ClearBlue Mineral System Cell and Tee
Mineral cell with visible electrodes

Hot tub ionizer cost

There are several hot tub ionizers on the market with varying costs. They range from $300 to $700, depending on the brand. The ClearBlue Mineral System is a popular option that costs $399.99.

Hot tub ionizer installation

Installing a hot tub ionizer takes around an hour in most cases. You must remove the side panel and find a stretch of plumbing to glue in the tee. Then, you have to mount the controller in a place that allows the power and cell cables to reach. This video is a pretty good example of the process.

You may need to engage a hot tub tech to help, but it’s an easy job for them.

Hot tub ionizer maintenance

With a hot tub ionizer, you must regularly maintain the pH, alkalinity, calcium, and other water parameters. In terms of the system itself, the mineral cell needs to be changed every 1-3 years, depending on the hot tub size and the hot tub ionizer model.

If your water is high in calcium or dissolved solids (TDS), you may need to remove and clean the cell every 6 to 12 months to remove scale. You can use a metal file or scraper and don’t need to use chemicals or solvents.

Hot tub ionizer availability

The most popular place to buy a hot tub ionizer is with your original hot tub. Several brands of wooden hot tub install them in the factory. If your hot tub retailer doesn’t offer it, or you want to add it to your existing hot tub, you can order yours online or on Amazon:

Hot Tub Ionizer Online:

Hot Tub Ionizer with AMP Plug (for spa packs)

Hot Tub Ionizer with NEMA Plug (standard wall plug)

Hot Tub Ionizer on Amazon (both plugs available)