If a pool or hot tub isn’t properly cared for, it becomes a petri dish in which microbial life will thrive. As a potential breeding ground for disease, water in pools or spas requires chemistry that prevents bacteria and other microbes from taking over. While previously water treatment methods involved boiling or filtering water, a Swedish chemist named Carl Wilhelm Scheele discovered a way to isolate a substance with disinfectant properties called chlorine.
Found to be a powerful germicide, a handful of companies in England and the United States began to use it for water treatment by the mid-nineteenth century Though the widespread use of chlorine for water treatment didn’t begin until the early 20th century, chlorine began to be used as a way to keep pool water safe for swimmers. In 1910, Brown University first used chlorine as a treatment to sterilize pool water, reducing bacterial counts in its Colgate Hoyt Pool to zero. The 1920s saw several states require the use of chlorine as a means to sterilize swimming pools.
The introduction of saltwater pool treatment began in the 1960s in Australia, where it was seen as a simpler and less expensive means of generating chlorine to keep pool water clean. Introduced to the United States in the 1980s, this method became increasingly popular for treating swimming pools. There’s still debate, however, about which method is better for keeping swimming pools clean and safe, along with various advantages and disadvantages of each method of pool sterilization. For this reason, we’ll look into saltwater vs chlorine pools and hot tubs to discover the pros and cons of each.
Using Saltwater vs Chlorine for Pools & Hot Tubs
Chlorinating pool water with saltwater is gentler on the skin and eyes while not producing the strong bleachy odor typical of conventional pool chlorination techniques. This is largely due to the salt content in the water, similar to that within the human body’s cells. Saltwater pools are also less harsh because sodium chlorinators keep the distribution of chlorine more even, preventing chloramines from forming in the water. These irritants commonly occur in conventional pools, which require the addition of large amounts of chlorine to shock pool water every few days.
However, there are downsides to saltwater treatments. They’re more expensive, especially when it comes to hot tubs, and they require more maintenance to keep them sanitary. For example, when a saltwater pool’s temperature falls below 60?F (about 15.6?C), it won’t produce sufficient chlorine, allowing bacteria to form. Saltwater can also damage pools and hot tubs, leading to rust and corrosion of pool accessories and fittings.
To better understand the debate between saltwater vs chlorine pools and hot tubs, let’s dig a bit deeper into the advantages and disadvantages of each type of treatment.
The main difference when comparing saltwater vs chlorine pools involves the additional equipment needed for the former. Saltwater pools generate chlorine with either a saltwater generator or saltwater chlorinator, though chlorine levels are typically lower than in traditionally chlorinated pools. Conventional swimming pools require chlorine to be manually added whenever chlorine levels fall below.
Pros and Cons: Saltwater vs Chlorine Pools
Now, let’s take a quick look at the pros and cons of saltwater vs chlorine pools…
Pros of saltwater pools include:
- Has lower chlorine concentrations
- Less irritable to the skin
- Reduces costs as it requires fewer chemicals to maintain
- Requires less frequently
Cons of saltwater pools include:
- Additional equipment means greater electricity usage, raising operating expenses
- Corrosion due to salt water often damages pool liner, pool lights, and other pool fittings and equipment
- More expensive installation
- More likely to require professional assistance for repairs and maintenance
- Saltwater isn’t conducive to the growth of most plants and can make nearby soil barren
Pros of conventional chlorine pools include:
- Less expensive installation
- Less electricity usage
- Water won’t damage the pool or fittings
Cons of traditional chlorine pools include:
- Higher chlorine levels tend to dry out and otherwise irritate the skin
- Needs more regular maintenance
- Requires manually adding chlorine to the pool
- Tends to have a higher chlorine concentration
- Will require shocking with chlorine more frequently
As hot water reacts differently, it’s important to look too at the differences between saltwater vs chlorine hot tubs. Different minerals and chemicals are used in hot tubs as a result.
Pros and Cons: Saltwater vs Chlorine Hot Tubs
As with salt water swimming pools, spas have chlorine, resulting naturally from sodium chloride (aka salt). As such, there’s no need to add chlorine tablets or bromine tablets as they sanitize continuously, though it’s important to add an oxidizer to shock hot tub water and keep it clean. Generally, salt water hot tubs resist chemical changes, making alkalinity, calcium hardness, and pH issues less of a problem, and many more advanced models will automatically adjust to more demanding use. Like saltwater pools, the water doesn’t have that heavy chlorinated smell commonly associated with chlorinated swimming pools, and this water is kinder to a hot tub user’s skin.
Like saltwater pools, hot tub equipment will corrode more quickly over time in salt water, while salt chlorination cells must also be replaced every couple of years. They’re also much more expensive initially, requiring a saltwater generator. However, over time saltwater hot tubs tend to be less expensive, as they require fewer chemicals. Yet, at lower temperatures of 60?F (about 15.6?C) or less, salt water hot tubs automatically shut down and then won’t be able to generate adequate amounts of salts, which may then result in bacterial growth.
In contrast, a chlorinated hot tub won’t cause fixtures or accessories to corrode as readily, and there’s no need to keep track of the water temperature. They’re also easier to maintain, as they don’t require a saltwater generator, though they do need occasional testing of chlorine levels and other chemistry to ensure they’re safe to use. As chlorinated hot tubs contain higher chlorine levels than saltwater ones, they’ll contain fewer disease-causing microbes, making them less likely to spread disease. The pungent odor and eye and skin irritation from chlorine hot tubs make them less comfortable, especially the longer a user remains in the water.
Contact the Pool & Hot Tub Experts at Halogen Supply
To learn more about the differences between chlorine vs salt water pools and hot tubs, or the equipment and chemicals required to maintain either, contact Halogen Supply today!