One of the myths about saltwater pools is that they don’t use actual chemical chlorine. This is not true. While a saltwater pool uses a chlorinator to produce sodium hypochlorite (chlorine) from salt that is added to the system, it still requires actual chemical chlorine at times to operate correctly.
While the amount of chemical chlorine you need to use in a saltwater pool is relatively minimal, it still does need to be used at times.
Let’s take a closer look…
Do You Use Chlorine in A Saltwater Pool?
There are several times that adding chemical chlorine to a pool is required. Specifically, a saltwater pool requires chemical chlorine in either liquid, tablet or crystal format:
When the pool is being opened in the spring: Over the winter, a pool requires very little chlorine since the temperatures (depending on where you live) are lower and thus less chlorine is needed. In the spring when the pool has little to no active chlorine left, you add a large amount of chlorine to the pool to shock it and then the saltwater pool chlorinator does its part to create chlorine and keep the water chemistry in line.
During the summer pool season: More chlorine is required in a pool when the pool is heavily used, during periods of hot sun or heavy rain, during algae outbreaks and other instances. Sometimes a saltwater pool system needs a bit of help maintaining reasonable chlorine levels and adding chemical chlorine does just that.
When you have a problem with the chlorinator: Speaking from experience here, when your chlorinator is giving you trouble or when the salt cell suddenly dies and you’re waiting a few days or longer for the replacement, you might need to use chemical chlorine in the meantime to keep the water chemistry right. In this case, the sooner you get the chlorinator up and running again, the better (and cheaper) it is.
The good news is that manually adding chlorine to a saltwater pool is not a regular occurrence in my experience. The flipside is that adding chlorine manually to a pool needs to be done properly to avoid bleaching your pool liner or damaging the chlorinator salt cell by running concentrated chlorine through it.
Having said that, what types of chlorine can be added to a saltwater pool and how should you add it?
Can You Put Chlorine Tablets In A Saltwater Pool?
Yes, you can but care needs to be taken. First off, handle chlorine tablets while wearing gloves and try not to make contact with your skin. It’s a chemical, is concentrated and can irritate skin.
Secondly, follow instructions in terms of how to actually add it to the pool and in terms of the dosage to be used.
Our first pool company told me to put a tablet one at a time into the skimmer basket to dissolve it but suggested putting it inside an old sock or some pantyhose to slow down the rate of dissolving. You certainly don’t want to simply drop the tablet into the pool to sit on the bottom of the pool and dissolve as it could stain the pool liner due to its high concentration.
With a saltwater chlorinator, you do have to be careful about putting large amounts of chemical chlorine through the salt cell as it can damage it over time. The salt cell was designed to produce its own chlorine rather than relying on chemical chlorine.
If you have a pool heater installed, you do also want to be careful with adding chlorine directly into the system through the pump. Highly concentrated chlorine can damage the seals. This is why you don’t want to pour liquid chlorine directly into the skimmer.
Speaking of which…
Can You Put Liquid Chlorine In A Saltwater Pool?
Yes, liquid chlorine can be added to a saltwater pool. But as above with chlorine tablets or crystals, care needs to be taken in terms of handling and actual usage.
When our first pool company opened our pool each spring when we were still paying them to do so, I watched out the window to learn about the steps involved. Once the pool chlorinator and pump was set up and turned on, they would pour a large plastic container of liquid chlorine into the shallow end of the pool to shock the pool. They would simply put the container on the ground, take the cap off and turn the container over on its side to empty into the water.
Personally I think it makes more sense to walk an extra 15 feet or so to the deep end and dump it in there closer to the main drain where it can be circulated throughout the system quicker, but that’s just me using what I think is common sense and not based on any proof.
If you’re using liquid chlorine I’d suggest pouring it into the deep end with the pump running to ensure it quickly mixes into the system.
As mentioned above I’d avoid pouring liquid chlorine directly into the skimmer as it’s highly concentrated and would still go through the pump, heater and chlorinator in a highly concentrated form that could damage the system over time.
What About Chlorine Powder For Pool Usage?
Chlorine powder still gets sold in large buckets as well as in small packets called Shock. While you want to follow specific product instructions, in my experience using these products involves filling a large plastic bucket with water – I usually just scoop water right out of the pool – adding in the desired chlorine powder, and then stirring it.
I then let the bucket sit for awhile so that the powder completely dissolves. Then I pour the entire bucket directly into the deep end of the pool with the pump running. The water might get cloudy for a bit but it usually dissipates quickly as it goes through the pool system.
Conclusion
- Despite what you may have read, you do use chlorine in a saltwater pool and typically add it to the pool when opening or closing a pool or during heavy periods of sun or rain to keep pool chemistry in check.
- Always follow instructions for adding liquid, tablet or crystal chlorine or Shock to the pool since it’s typically highly concentrated and can irritate skin and damage or bleach pool liners with misuse.
- Liquid chlorine gets used up quickly whereas buckets of crystals last longer because they are concentrated and have to be mixed with water. Shock is convenient because it’s in highly concentrated packets but also tends to be relatively expensive as a result.
- Want to learn more about saltwater pools and how they compare? Check out my What Is A Saltwater Pool post to learn more.