A salt water pool is similar to a regularly chlorinated pool but there are some components specific to it that other pools don’t have. There are also some similar pool components that in practice are a bit different for salt water pool owners that you should be aware of in my experience.
Here are 7 aspects of a salt water pool you will learn once you become the owner of one.
Pool water salt
A salt water pool generally requires around 1 teaspoon of salt added for every 1 gallon of water. Salt doesn’t evaporate or wear out but does need to be replaced every year due to various aspects of water loss in the pool.
The salt used in a salt water pool should be the one specified by your chlorinator manufacturer or recommended by your pool company. While pool salt-specific products exist, many salt water pool owners simply use white pellet salt made for water softeners.
While white pellet water softener salt can generally be used in a salt pool unless your chlorinator says otherwise, it won’t dissolve right away when you pour an amount into the pool. As it was designed for water softener usage, the pellets will dissolve slowly over a matter of many hours or even up to a day if you dump a whole bag in the water.
Pool-specific salt on the other hand is granular and although coarser than table salt, will tend to begin dissolving right away when it’s added to the water.
I’ve used both and they each work fine but regular water softener salt is about half the price of pool salt.
Don’t use crystal rock salt that looks like it has a pinkish or grayish tinge as it is not meant for pool use. Also stay away from water softener salt brands that have other ingredients added to control copper or calcium as that’s specifically formulated for a water softener.
Add your salt with the pump running to more quickly circulate the salt throughout the water.
Salt chlorinator
The salt chlorinator is the actual control box or computer if you will, that manages the salt cell and tells it when to turn on and off. The only time the salt cell can produce chlorine is when the pump is running and when the chlorinator tells it to turn on. So the pump can be running but the chlorinator may or may not be creating chlorine at the time depending on how you have the chlorinator set.
The chlorinators sold today enable you to do many things automatically that old-school pool owner must do manually. My first generation chlorinator just had an on off switch, chlorine dial to tell it how often to make chlorine and a few lights. I had to turn the pump on and off manually.
Newer salt chlorinators can offer a number of potential benefits and automation tools depending on the model you buy. Typically you can set the chlorinator to produce chlorine a certain percentage of pump run time from 0% – 100% and you may have scheduling features to run your pump, heater, lights, water features and other pool-related items on a schedule.
Some higher end chlorinators can automate many other aspects of running your pool so you don’t have to do it yourself.
Salt cell
The salt cell is the device that actually converts salt to a form of liquid chlorine through a process called electrolysis. It is installed as part of the pool’s plumbing on the return line back to the pool behind the pump, filter and heater.
Inside the cell is a series of vertical metal plates which receive an electrical charge when the chlorinator is turned on. When water passes through the salt cell, the metal plates inside the cell electrify the dissolved salt and convert it to chlorine to sanitize (clean) your pool.
A salt cell will typically last for 3 – 5 years depending on how well you take care of it and how much it is used. Each cell has a lifespan so the more it’s activated and producing salt the sooner it will need to be replaced.
The chlorine that is produced by your salt water chlorinator is softer and cleaner than commercial liquid or powder chlorine products and also doesn’t have the associated strong chlorine smell that we remember when swimming in a regularly chlorinated pool. The water in a chlorinated pool tends to be easier on the skin, eyes and clothes than older style chlorine pool water.
One excellent feature to look for when choosing your salt chlorinator: Pick one with a reverse polarity feature which automatically cleans your salt cell by ridding the metallic plates of calcium and other mineral buildups that hinder cell performance. It saves you cleaning your salt cell manually and may extend its shelf life.
Stabilizer
Stabilizer is a coarse powder that gets manually added to salt water pools to protect the chlorine from the UV effects of the sun. Chlorine can die very quickly in direct sun and stabilizer is a sunscreen of sorts to help protect against this. Stabilizer is also known as cyanuric acid or CYA.
While many crystal and puck chlorine products are already stabilized and have it built in, stabilizer needs to be manually added to a salt water pool as the chlorine produced from salt does not have any. I sprinkle my stabilizer directly into the side skimmer with the pump running very slowly to distribute it quickly. Your chosen brand may require a different method of delivery.
In a salt water pool, stabilizer should be maintained between 70 ppm – 80 ppm in an outdoor pool. Given its coarseness and the fact that it doesn’t dissolve right away, stabilizer should be added to the pool slowly according to manufacturer labeling.
pH level
The pH (potential of hydrogen) measures the acidity or basicity of the pool water. All pools require pH kept between 7.2 and 7.8 where the lower numbers represent something that is acidic and the higher numbers represent something alkaline. A pH of 7.0 is totally neutral.
A battery and stomach acid is very acidic whereas drain cleaner at the other end is very alkaline. In the middle is water and blood, to give a few examples.
Salt water pool owners are more likely to need to lower pH than raise it. Salt water pools have a tendency to see the pH creep up rather than go down. pH typically goes up because of a loss of CO2 in the water, adding non-stabilized chlorines which are sometimes required even in a salt water pool, or adding too much acid to the water. These events can all help to spike the pH level so be careful.
Sanitation
Sanitation refers to keeping the pool clean and sanitized for swimming. Even in a salt water pool, the sanitizer of choice is chlorine.
In any chlorine or salt water pool the desired chrorine level is suggested to be 1 ppm – 3 ppm. Some people suggest 2 ppm – 4 ppm is a better range, and thus keep it a bit higher.
Even in a salt water pool, chlorine is needed. Your salt water chlorinator converts dissolved salt in the water into liquid chlorine to sanitize the pool. So even though the pool is called a salt water pool, it still has chlorine in but in a slightly different form.
Plus, several times per year you will need to add actual chlorine of some kind to the water. Typically this is in the spring when opening the pool and again in the autumn at winter closing. You may also choose to shock the pool during the pool season to assist the chlorinator to keep up with increased chlorine demand from hot sun and pool usage.
NOTE: Shock is a highly concentrated form of chlorine often sold in small pouches as well as buckets that you add to a pool – including a salt water pool if needed – to quickly raise (ie. shock) the chlorine level upwards.
Algae
Algae occurs largely due to a lack of chlorine in the pool and can be exacerbated by incorrect pH and alkalinity levels too. While algae can occur in any pool, for salt water pool owners one thing to keep in mind is that pH tends to drift upwards more so than in a regularly chlorinated pool. Water balance is very important for any pool and keeping chlorine levels inline will prevent algae growth.
While I’ve read plenty of articles online about getting rid of algae by dumping large amounts of chlorine into the pool to clean it up I’ve never had success with this method. I guess if you dump enough chlorine in a salt water pool, it’ll eventually do the trick but what’s the point?
Why not use a bottle (or two if needed) of algaecide and fix it properly, most likely faster, and definitely cheaper? I’ve spent over a week on occasion dumping chlorine in a green pool trying to fix it and it doesn’t work. I’ve watched my pool company open my pool in the past by dumping liquid chlorine in and days later the pool is almost as green as it was when they started. At the time, I didn’t know enough about pools to understand how to fix it myself but I do now.
When you use algaecide, add it with the pump running and the next day vacuum the pool. Clean or backwash your filter and vacuum again. Repeat until the pool is clean. But remember to ensure that pool chemistry is balanced and that you have enough chlorine in the pool otherwise you’re pushing a boulder up a hill.
NOTE: When I talk about a green pool, I literally mean the water looks like pea soup and looks like a swamp. In my experience, I’ve never come close to killing that much algae with chlorine and have always ended up using a bottle of algaecide and in a few cases, a second bottle of algaecide.
Summary
Water chemistry is important in any pool but given the automated nature of a quality salt water chlorinator system, the good news is that they generally keep water balanced and automate many tasks you’d otherwise have to do manually. Become familiar with your salt water pool system and each component to understand how each works and how each aspect of your water ties into one another.
Over time you’ll be able to troubleshoot on your own which is cheaper and quicker than relying on your pool company. That way you only have to rely on them for important stuff that you can’t figure out yourself.
