There are two options to sanitize a swimming pool – freshwater with added chlorine or use a salt water chlorine generator.
Salt Water Chlorine Generators automatically and continuously produce the right amount of chlorine to fully sanitize your pool water and keep your family safe.
The salt chlorine generator controller passes a very low voltage, high electric current through the salty pool water in the chlorinator cell to produce free chlorine. The free chlorine sanitizes your pool water by destroying algae, bacteria, viruses and other contaminants. These dead contaminants are removed from the pool by the filtration system.
Every time your pool pump operates, the salt chlorine generator will automatically produce a sufficient amount of chlorine into the pool to keep the water sanitized and sparkling clean. There is no requirement to manually add chlorine to the pool. This gives the pool owner a very low-maintenance swimming pool and provides a high level of assurance that your pool is continuously sanitized every day even when you are on a long vacation.
Table of Contents
What is a Salt Water Chlorine Generator?
A salt water chlorine generator is the last piece of equipment in a pool filtration system. It’s connected inline into the plumbing after the filtration unit and water heater (if you have one). Water comes from the outflow of the filter and passes through the salt chlorine generator before it flows back into the pool.
There are two parts to a salt water chlorine generator – the control panel and chlorinator cell.
The control panel is mounted on the wall above the filtration system and is connected to the mains power supply. The control panel contains an electronic timer and is connected to the pump to automatically switch it on and off according to the timer settings.
This controller panel also contains a control to adjust the amount of chlorine produced. The controller has an electric cable that connects to the salt generator cell. It passes a low voltage, high electric current through the cell to produce chlorine by way of chemical electrolysis.
The salt chlorinator cell contains a number of charged metal plates that splits the salt water into chlorine which immediately dissolves in the water. The cell unit is installed inline with the filter outflow so filtered water flows through the salt generator cell before going back to the pool.
Benefits of a Salt Water Chlorine Generator
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Very Low Maintenance
Add a couple of bags of salt each year. Clean the cell at the beginning of the swim season. Replace the worn cell every 5 or more years.
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Use Less Chemicals
Don’t need to purchase chlorine or pool shock. The salt chlorine generator automatically regulates and generates the correct amount of chlorine for your pool, even in the middle of the night. There is no guessing how much chlorine to add to the pool.
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Easy to Maintain Water Chemistry
The pool water is much easier to balance and maintain with salt water chlorination. The variation in chlorine in your pool is what actually causes variations in pH and total alkalinity.
Salt chlorine generation is automated and continuously released into the pool in small doses resulting in smaller and fewer fluctuations in pH and total alkalinity levels. Overall, this is what makes the pool water much easier to manage.
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Low Operating Cost
The cost of operating a salt water chlorine generator is minimal and you will not notice the impact on your power bills. You may even be able to save money by running the pump an hour less each day.
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Health Benefits
Salt chlorine generators have become very popular because of the health benefits. Salt water pools are easier on the skin, eyes and swimwear because there is a lower level of continuous chlorine generation rather than peaks of chlorination with manual chlorination.
Swimming in salt water pools helps to open up pores, remove excess bodily oils, kill acne-causing bacteria, heal small cuts and abrasions and soothe joint & muscle pain.
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No Chemical Smell
The pool does not smell of chloramines as the chlorine generation is continuous and always at the correct level of sanitization.
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Use in Spas, Hot Tubs and Plunge Pools
Why not attach a salt chlorine generator to your hot tub, spa or plunge pool. There are models for every application and size of pool.
Salt Water Chlorine Generator Maintenance
The salt chlorine generator electrolysis cell requires cleaning every year. The best time to clean the cell is at the beginning of the swimming season in Spring.
Some salt chlorine generators have a self-cleaning option. There is a control on the panel that reverses the polarity of the voltage supplied to the cell. The reversed voltage helps to remove the calcium scale that accumulates on the electrode plates.
Please read our article on How to Clean a Salt Chlorine Generator Cell
The Cost of a Salt Water Chlorine Generator
A salt chlorine generator costs between USD$600 – $1500 depending on the brand name, the type of generator and capacity of the model. You can purchase a chlorine generator for an above ground pool or inground pool.
The cost of the initial installation is extra and varies depending on the type of filtration system.
A bag of pool salt costs under $10. Each year you will need to add a couple of bags to the pool to maintain the salt level within the desired salinity range.
The initial cost may deter some pool owners from installing salt chlorine generation. However, over the long-term you will save more money on less chemicals and pool maintenance.
How Long Does a Salt Chlorine Generator Last?
The control panel will last for years. I have seen some panels in operation for over 20 years and still work well. However, the technology has changed from analogue to digital electronics. The old-style analogue panels used a rotating timer dial to set the times when the pump and chlorinator operate. The new digital panels use a keypad and LED screen to input and display the pump operation times and chlorinator settings.
So if you have an old analogue panel you will need to replace the chlorinator system to a new digital model. You will not be able to get parts for an analogue system.
A correctly maintained salt chlorine generator cell has a normal life expectancy of at least 3 to 6 years. However, the life span will vary considerably depending on the use of the swimming pool. A salt chlorine generator cell that operates all year round, like in a tropical climate, will have a reduced cell life expectancy. A pool in a cooler climate which is used only during summer will have a higher cell life span.
When a salt water chlorine generator cell has worn out or failed it can easily be replaced by a home handyman. The cost of a replacement chlorinator cell is around $300 to $500. Simply order a new cell online for your brand of chlorine generator and follow the manufacturer’s installation instructions. Or maybe now is the time to upgrade the whole system to the latest digital technology.
How Much Salt Do You Put in a Salt Water Pool?
The concentration of salt required to achieve a satisfactory level of chlorination depends on the chlorine generator manufacturer’s specifications. Most chlorine generators operate with a salt concentration of 3000 to 7000 mg/l (ppm).
However, heated pools and outdoor pools in sub-tropical or tropical climates require a higher salt concentration to increase the chlorine output. This is to compensate for the extra chlorine evaporation from the pool. The salt level should be in the range of 5000 to 7000 ppm.
Add the correct amount of salt for the volume of your pool as per the following formula.
Salt quantity (kg) = water volume (m3) x Salt Concentration (mg/l) / 1000
1 cubic meter (m3) = 1000 litres of water
Example
Volume = 60 cubic metres (60,000 litres)
Desired Salt concentration = 5000 ppm (mg/l)
Salt quantity (kg) = 60 x 5000 / 1000 = 300kg
Salt comes in 20kg bags, so you need 15 bags of pool salt.
How to Add Salt to a Pool
Never add salt into the skimmer box.
The undissolved salt will block your plumbing pipes, increase pressure and potentially damage the filtration system.
Turn on your pump with the chlorinator switched off.
Position the bags of salt evenly around the edge of the pool.
Cut open each bag and empty the contents into the pool water.
Add the recommended amount of pool stabilizer (cyanuric acid) into the pool. The normal level is 30 to 60 ppm. The start-up quantity of stabilizer will be around 2kg for an average inground pool.
Use your pool brush on the telescoping pole to push the salt around the bottom of the pool until it is fully dissolved.
Run the pump for a full filtration cycle to fully dissolve the salt and stabilizer. A full cycle is when the pump has turned over the entire contents of the pool which usually takes at least 6 to 8 hours depending on your pump.
The next day after all the salt has fully dissolved turn on the salt chlorine generator to start producing chlorine.
Please read our article on How to Fill a Salt Water Pool
Does a Salt Chlorine Generator use more Electricity?
All swimming pools need to be filtered by running a pump. Adding a chlorinator unit into the plumbing does not affect the pump at all and makes no difference to the amount of electricity usage. The chlorine generator cell uses a low voltage current to split the salt into chlorine which will add a small extra cost to your power bill. However, using a chlorinator means you don’t have to buy chlorine and other chemicals for the pool saving you money.
How Salty is a Saltwater Pool?
The concentration of pool salt is normally 3000 to 7000 ppm for a salt water pool. Compared with 35,000 ppm concentration of salt found in seawater. The concentration of salt in a pool is about equal to the salinity of the tears in your eyes so opening your eyes underwater will be not be uncomfortable. And most people cannot taste the salt in the pool water as the concentration is too low.
Common Problems with Salt Chlorine Generator
Overall, the benefits of salt chlorine generation far outweigh the minor issues associated with a saltwater chlorination system.
Metal Corrosion
Aluminum and other metal fittings are slightly more susceptible to corrosion in salt water than in freshwater. However, the pool water salinity concentration is only 10% of seawater so metal corrosion is only a very minor issue in a swimming pool.
The only way to avoid corrosion is to use powder-coated metal parts on ladders, rails and pool light fittings. Some people prefer brass fittings as they corrode more slowly than other metals.
High or Low Chlorine Level
Once the chlorinator control panel is set the system will produce the correct level of chlorine every day. However, when pool owners change the operating times of the pump, they can cause the generation of too much or too little chlorine. Regular water testing and adjusting the chlorine output control will fix this issue.
Vinyl Liner Damage
Saltwater can be harsher on vinyl liners than other pool linings. This is only an minor issue and I have not seen any significant issues with using saltwater in vinyl lined pools.
Conclusion
I have personally owned salt water pools and have experience with salt water pools for over 30 years. I recommend saltwater chlorine generation because it not only works very well but it’s inexpensive to install, operate and maintain.
A saltwater pool virtually looks after itself on autopilot.
The salt water concentration is very low and similar to saline solution for washing your eyes so it cannot irritate your skin or eyes. And you can hardly taste the salt in the water.
Other sanitation options are complex, more expensive and require more of your time to operate effectively.