In today’s market, five different manufacturers produce Salt-System Sanitation options for hot tubs. One of them is also suitable for swim spas with capacities generally in the 1,500 – 2,500 gallon range. We have listed them all, noting some of their characteristics and important considerations below.
Overview
| Blu Fusion | Freshwater® Salt System | inclear™ | Onzen™ | Saltron Mini | |
|---|---|---|---|---|---|
| Manufacturer | BluWater Technology | Watkins Wellness | Gecko Alliance | Arctic Spas | Solaxx |
| Salt | Sodium Bromine (NaBr) | Sodium Chloride (NaCl) | Sodium Bromide (NaBr) | Sodium Chloride (NaCl) | Sodium Chloride (NaCl) |
| Sanitizer (Common Name) | Bromine | Chlorine | Bromine | Chlorine | Chlorine |
| Sanitizer (Chemical Name) | Hypobromous Acid | Hypochlorous Acid | Hypobromous Acid | Hypochlorous Acid | Hypochlorous Acid |
| Warranty | 3-Years | 1-Year | 1-Year | 2-Years | 1-Year |
| For Use in Hot Tubs | Yes | Yes | Yes | Yes | Yes |
| For Use in Swim Spas | Yes | No | No | No | No |
Important Considerations
Longevity
Warranties are often a good indicator of the longevity of a manufacturer’s products. Many people think warranties protect them. The truth is manufacturers first developed warranties as a means to protect themselves. Warranties make it very clear (legally clear) when their responsibilities stop.
Cost
There are really two ways to look at cost. One is the initial cost to purchase a product. The other is the long-term cost to own and operate a product. The second includes both the initial cost and the operating costs over the life of the product. Long-term cost reflects the true cost of a product.
The printer industry is a classic example of low initial cost but very high long-term cost. Printers are cheap but their cartridges are expensive – and you have to keep buying them.
Unfortunately, Watkins used the printer “model” with their Freshwater Salt system. The initial cost is relatively modest, but you have to replace their electrodes 3x a year, typically at a cost of around $100 every time. Over the 10-year life of a typical hot tub, you will spend $3,000 on replacing electrodes with the Freshwater Salt System.
Warranty
Most often the electrode cell (where the sanitizer is produced) is not part of the standard warranty. Only Blu Fusion includes its electrode cell in its 3-Year warranty. The other 4 manufacturers either specifically exclude the electrode cell or provide no more than a 30-day warranty. And, as I mentioned above, you have to replace it every 4 months with the Freshwater Salt System.
Ease of Use
Though several manufacturers have some pretty lengthy Operating Manuals, fundamentally, operating a hot tub with a salt-system is no different than any other spa. You MUST test your spa water for proper chemistry at least once a week. You are still testing for the same 4 items as with any spa:
- Sanitizer, either chlorine or bromine
- Chlorine: 2 – 4 ppm
- Bromine: 3 – 5 ppm
- pH: 7.2 – 7.6
- Total Alkalinity: 80 – 120 ppm
- Calcium: 150 – 250 ppm
The first two are critically important.
- Chlorine and bromine are both sanitizers and oxidizers.
- As sanitizers they are killing bacteria and other pathogens that might be present in your spa.
- As oxidizers they are removing biologic waste (dead bacteria, skin cells, etc.) that are a food source for bacteria.
- It is important to keep your pH in the proper range for two reasons.
- Chlorine rapidly loses its ability to kill bacteria as pH rises. Even at a pH of 7.8, chlorine loses 75% of its killing efficacy.
- By the way, this is not true of bromine. Bromine’s ability to kill bacteria is only minimally impacted by high pH.
- High pH will allow calcium scaling to occur in your hot tub and particularly in the salt-system electrode.
- Chlorine rapidly loses its ability to kill bacteria as pH rises. Even at a pH of 7.8, chlorine loses 75% of its killing efficacy.
Installation
The first four salt-systems are all installed “in-line.” They are integral to the spa’s plumbing, hence out of sight and under the spa shell. However, the Saltron Mini has an electrode that is simply hanging in the spa water, usually near the filter. It looks like an add-on to the spa. On top of that, Solaxx says this in their Operating Manual, “The Saltron™ MINI over the wall cell should be removed whenever the spa is in use.”
Other Comments
Bromine is the superior sanitizer in hot tubs. Unlike chlorine:
- It’s ability to kill bacteria is not impacted by high pH.
- It does not off-gas at hot tub temperatures.
- Bromine is a liquid at spa temperature while chlorine is a gas.
- Bromine’s by-product, bromamine, is also an effective sanitizer (with little odor) while chlorine’s by-product, chloramine, has no ability to kill bacteria (and is quite noxious).
Some chlorine-based salt systems, notably the Freshwater Salt System, often require the addition of either dichlor or sodium hypochlorite in order to maintain the recommended level of chlorine.
Cal Spas installs the Saltron Mini and calls it Cal Salt™ Filtration.
Thanks for reading.
