Salt water pool systems have more responsibility than regular chlorine pools because there is more equipment involved. Salt water pool owners don’t necessarily have much experience with chlorine in liquid or powder form since we generally don’t need to use it regularly.
Plus we have an expensive salt cell and chlorinator that need to be considered when adding anything into the pool. Some of these chemicals can damage the cell if not added to the water correctly.
With that in mind, here are 6 ways you damage your salt water pool that you need to avoid.
Pouring chlorine directly in the skimmer
Don’t ever dump concentrated chlorine products directly into your skimmer. The skimmer leads directly to the pump which means you’d be sending a highly concentrated amount of chlorine into your salt cell which can damage it.
Salt water pool owners don’t necessarily have much experience using regular chlorine like other pool owners do. While chlorinated pools need chlorine added weekly, a salt water pool owner may only add chlorine once in the spring during opening and perhaps at closing, or not at all if they use a pool company for both tasks.
So when you need to add chlorine to a salt water pool, you may assume you just dump it in. Follow the instructions on the product label because it probably isn’t the case. Many crystal or powder products added to a salt water pool work best when they are added and mixed in a bucket of warm water first and turned into a slurry ie. a mixture.
Chlorine is a bleach and it can stain and discolor your pool liner so it’s always best to read the instructions before doing anything. But never dump concentrated chlorine of any kind directly into the skimmer or into the pump. The salt cell needs to be protected from highly concentrated chlorine or shock going directly into the pump.
Pouring chlorine powder directly in the water
While sprinkling a small bag of shock into the pool water directly isn’t necessarily going to cause trouble, pouring a large amount of crystal chlorine directly into the water isn’t something you should do.
Read the instructions on the label of the container but if you are adding liquid chlorine to a pool, it can generally go directly in the water in the deep end. But large amounts of powdered chlorine works best when it is first mixed in water and then poured into the deep end with the pump running.
Pouring a large amount of powdered chlorine into the pool isn’t a great idea because it can either stick and clump or it can float for awhile and end up around the sides of the pool and bleach the liner.
Pouring powdered CYA directly into the skimmer
Pouring any large amount of powder quickly into the side skimmer isn’t a great idea but adding CYA (stabilizer) this way is not a good idea at all as it can clog the system and end up blocking your pipes.
Many powdered shock products include stabilizer in the formulation. Stabilizer helps to protect chlorine from the damaging effects of the sun. So again, salt water pool owners don’t have much experience with this since we generally don’t use commercial chlorine products. Our salt water chlorinator makes chlorine with salt.
So we need to manually add CYA to the pool water to protect chlorine produced by our chlorinator. The question that many salt water pool owners ask regarding stabilizer is…
Why isn’t my CYA stabilizer dissolving?
Depending on the product you might have powdered CYA or puck form. Stabilizer by its makeup tends to dissolve very slowly in water. It’s often recommended to sprinkle powdered stabilizer very slowly into the side skimmer with the pump running so that it goes directly into the system. It’ll get churned up by the pump and quickly distributed throughout the pool.
Again, the key here is pouring it slowly into the skimmer.
My pool company suggested putting the required amount of stabilizer in an old pair of pantyhose or some other porous clothing and sticking that in the skimmer to slowly dissolve. I don’t feel comfortable with that so I sprinkle it in manually and very slowly with a scoop.
Letting your salt level get too low
Salt level in your pool should be between 2,700 and 3,400 ppm with 3,200 often seen as the ideal. That way it’s on the higher end and knowing that salt content drops in a salt water pool over time, it’s high enough that you shouldn’t have to constantly fight to keep it high enough.
The lower your salt level, the more your system struggles to produce chlorine. For some chlorinators a low salt warning will alert you when salt goes down around the 2,700 ppm area and below that, the system will eventually shut down chlorine production to protect the salt cell from damage.
If your chlorinator has an instant salt reading, check it every week or so to see what it is and monitor it as it drops. If you don’t have this feature, get some decent quality pool test strips that include salt testing so you can ensure you are in the right range.
Also get your pool company to test your water every few weeks during the summer pool season to see how your salt level is changing. I find that salt gets added to my pool twice per season: Most salt goes in during the spring time opening and then about half that amount gets added mid way through the summer again.
Not cleaning your salt cell properly or at all
Modern salt water chlorinators increasingly include a feature called reverse polarity which auto cleans the salt cell from minerals like calcium that attach themselves to the metal plates of the salt cell. Over time, calcium and other minerals stick to the plates as water passes through the cell and will eventually degrade its ability to properly convert salt to chlorine.
So chlorinator manufacturers like Hayward added a feature that regularly reverses the polarity to force these minerals off the metal plates of your salt cell to keep it clean. It saves you manually cleaning the cell using chemicals which is what you’re going to have to do if your chlorinator doesn’t have the reverse polarity feature.
The good news is that as time goes on, chlorinator manufacturers are including this feature standard on their products.
If you don’t have this auto cleaning feature, you should check with your salt cell manufacturer to see how they recommend you clean your cell. At a minimum you should inspect your salt cell every few months of the pool season to see if minerals are building up on the metal plates of your cell. Keeping it clean will help you extend the life of your cell while ensuring it runs properly during its lifetime, too.
Improper concentrations of various products in the pool
While water balancing in a salt water pool tends to be easier to maintain than other pools, it still takes some work especially when things happen to throw certain metrics out of range. Whenever you add something to your pool, you need to first ensure you understand the ramifications, as adding something to raise or lower a value may also impact another.
Common examples include adding too:
- Much salt to your pool. Increasing salt in your pool is easy but decreasing it isn’t. To drop salt levels, you have to drain water from the pool and then add water again to dilute the salt content.
- Little salt which makes the chlorinator work harder to produce chlorine and may result in the system shutting down if salt gets too low.
- Much or too little stabilizer. This can negatively affect chlorine levels.
- Much sodium carbonate which will raise the pH to the point where water irritates the skin.
- Much muriatic acid which can lower the pH to the point that it stings your eyes when swimming.
- Much sodium bicarbonate which can raise the total alkalinity and throw pH out of whack, leading to cloudy water and itchy skin and eyes.
- Much muriatic acid which lowers the total alkalinity to the point where the pH drops too far and chlorine is negatively affected.
- Much stabilizer (CYA) which can negatively affect chlorine’s ability to sanitize the pool.
- Little stabilizer which makes it harder for chlorine to survive the UV rays from the sun resulting in more chlorine usage.
- Much calcium chloride which makes water too hard, adding scaling and calcium to the pool and equipment. When water becomes too soft though, it’s more difficult since there is no chemical to harden water. You’d need to speak with your pool company with a water sample for advice.
Summary
While a salt water pool is generally easier to maintain than a chlorinated one, it still requires work and properly adding chemicals to the pool to keep water balanced. Adding a chemical the wrong way can have a negative impact on your pool equipment and adding too much or too little of a chemical may also have negative implications on one or more other aspects of pool balancing.
Check my charts page on pool chemistry to learn more about the importance of each major aspect of water balancing in your salt water pool to keep learning.