The Complete Story of Salt Chlorination

A recent most common trend in the swimming pool industry over the last few years has been the popularity of saltwater swimming pools systems. Many questions about saltwater swimming pools have been inundated on us in the swimming pool industry. Hopefully this information will help give better information on a salt water pool.

What is a saltwater pool?

A saltwater pool is a pool which has a chlorine generator that provides on-site production of chlorine.
Chlorine generators reduce the need to purchase and apply chlorine to your pool on a regular basis. Basically, instead of adding chlorine on a regular basis, you add salt periodically when the salinity is lowered due to addition of fresh water, which is converted to chlorine.

How does it work?

The way it works is: Salt is added to the pool and the saltwater passes through an electrolytic cell, where electricity is used to separate the sodium and chlorine molecules. Which in then produces hypochloric acid, the killing form of chlorine. Once the chlorine is used it combines with sodium molecules and returns to salt and the whole process begins over again.
Often times, pool companies seem to not mention the complete story when selling a saltwater system, but it is important that a pool owner understands the pros and cons of salt water system.
Based on our professional experience listed is the pros and cons of salt water systems:

 

Pros of saltwater pools

The pool water is softer on your skin

This is one the biggest advantages of a salt chlorine generator. Owners of salt chlorine generators talk about how soft and smooth the water feels and how it doesn’t dry out or irritate their skin.

More consistent water quality

A more consistent water quality is maintained because the unit is continuously chlorinating when the pump is in operation. Instead of throwing in traditional chlorine where the chlorine levels rise and fall until the pool is serviced next.

Less eye irritation

Swimmers normally report less eye irritation when using chlorine generators. Which is great when you have lots of little swimmers.

Less need to purchase chlorine

There is less need to purchase chlorine since the chlorine generator is producing chlorine. Situations that call for chlorine to be added is due to extremely high water temperature, heavy swimmer load, rain, etc., the chlorine generator is not working, and chemical imbalance can all be factors of why chlorine could be added.
No need to store and handle chlorine
Other than the rare situation listed above, storing and handling of chlorine will be limited.

 

Cons of saltwater pools

Initial cost

Chlorine generators are often sold as a cost-savings system, which is not a true statement in most situations. The installed price for a high quality residential chlorine generator is typically $1,500-$2,000. You do no longer have to buy chlorine, and salt is less expensive than chlorine, but at $1,500-$2,000, you could buy chlorine for 5-6 years.

Cell replacement cost

Chlorine generators are mechanical devices, and as with any mechanical device—they can break down. The most common failure of chlorine generators is the salt cell, which typically last 5-7 years (depending on use and maintenance) before needing replacement at an average cost of $600-$900.

A saltwater pool is not chlorine-free

A “salt water pool” is still a chlorine pool. The chlorine production in a saltwater pool is essentially sodium hypochlorite (liquid chlorine). If you are truly allergic to chlorine, then this is not the system for you.

Increase in electrical costs

A chlorine generator only produces chlorine when the pump is operating, so it is important to operate your pump a sufficient amount of time to produce the amount of chlorine that is needed for your pool. This amount of time will increase under the following conditions: high water temperature, heavy swimmer load, pets that swim, rain, chemical imbalance, etc.
Running your pump for longer periods of time will result in an increase in electrical costs.

Salt can be corrosive

Salt can be corrosive to coping (especially stones that are porous or a softer stone), stone waterfalls, decks, and any metal (such as diving board bases, pool ladders, slide legs, poolside furniture, stainless steel filters, house paint etc.). To help slow down this corrosion process, the application of a penetrating sealer to coping and stone waterfalls seems to help. This penetrating sealer needs to be applied at a minimum of once annually. In addition, we recommend rinsing off your coping/decks/metal with fresh water after using the pool.

Not environmentally friendly

Due to the salinity of the water and its potential harm to sensitive plants and fish, many municipalities have restricted the backwashing or draining of saltwater pools into the storm sewer system.

They do not provide complete pool care

Oftentimes owners of saltwater systems depend on the system to provide complete pool care—they do not. Maintaining your chemical balance is still very important as well as routinely cleaning your salt cell per manufacturer’s directions and schedule.

Water testing

Salt Chlorine generators only produce chlorine, they do not maintain the water chemistry of the pool. The pool water must still be tested and balanced on a weekly basis. It is also important to remember that salt raises the PH level during the process of producing chlorine, which means more muriatic acid will be needed to keep the PH in balance.

Cell cleaning/replacement

Like any mechanical device, salt chlorine generators must be maintained most manufacturers recommend that the system’s cell be cleaned every six months. Salt cells typically last 5-7 years, depending on use and maintenance. Salt cell replacement typically costs approximately $600-$900, depending on the manufacture of your salt system.

Can cause scale forming deposits on the tile, spa spillways & waterfalls

The use of salt can cause scale deposits to form on tile, spa spillways & waterfalls. Brushing regular running a stain and scale agent in the pool will help with having a scaling issue. It’s also important to remember in our service area and Texas alone we have really hard water.

Does not work in cold water

Chlorine generators do not produce chlorine when the water temperatures drop below approximately 58 degrees. When this occurs, the use of chlorine will likely be necessary in order to prevent problems.

 

Conclusion

Our overall opinion of salt chlorine generators is like anything else, it has pros and cons. We wrote this so you could have our professional opinion and you could take all the pros and cons into consideration. A saltwater system can be a great alternative to traditional pool chlorination if it is properly maintained.