Is There Chlorine In A Saltwater Pool? Can You Add Extra?

Saltwater pools are a popular alternative to chlorine pools, largely because they are seen as a low maintenance option.

Although saltwater pools require different maintenance to chlorine pools, both of these pool types achieve sanitation in a similar way.

In this article we will discuss whether or not there is chlorine in a saltwater pool, if you can add chlorine to a saltwater pool, and when it is appropriate to do so. We also include some information about how to choose a shock product for saltwater pools.

Is There Chlorine In A Saltwater Pool?

Many people assume that there is no chlorine in saltwater pools, but this is incorrect.

Although no chlorine products are added to saltwater pools directly, a machine known as a saltwater chlorine generator (or SWG for short) produces the chlorine that is found in saltwater pools.

By converting pool salt into chlorine through a process called electrolysis, saltwater chlorine generators maintain the recommended levels of free chlorine in saltwater swimming pools, which range from 2-4 parts per million (ppm).

So, even though the source of free chlorine is different, there is typically the same amount of chlorine in saltwater pools as there is in traditional chlorine pools.

Then Why Don’t Saltwater Pools Smell Like Chlorine?

You are still much more likely to notice a strong chlorine smell coming from a traditional chlorine pool than a saltwater pool, but this difference in smell is not actually due to the chlorine content in the water.

Strong chlorine smells in a pool are actually caused by chloramines, a compound that forms when free chlorine molecules combine with certain water pollutants. The strong chlorine smell occurs when free chlorine levels actually get too low.

In saltwater pools, the chlorine level is maintained by the SWG, rather than from infrequent additions of chlorine by the pool owner, so there is less likely to be low free chlorine and high chloramines, which give off the smell.

Can You Add Chlorine To A Saltwater Pool?

Because saltwater pools do contain chlorine, there are some cases where it is appropriate to add chlorine containing products to your pool. However, it is not recommended that you add chlorine to your saltwater pool as a substitute for proper saltwater pool maintenance.

Always ensure that your saltwater chlorine generator and its salt cell are functioning properly and have been thoroughly cleaned and descaled.

You should also be maintaining the manufacturer recommended salt level (typically 2,700-3,400ppm - test this regularly). If your pool is well maintained and working as normal, you do not need to add extra chlorine to achieve normal sanitation.

When To Add Extra Chlorine To A Saltwater Pool

You may choose to add extra chlorine to a saltwater pool if unsanitary conditions are developing.

After a period of neglect where your pool has not had adequate salt levels or enough chlorine being generated, you may want to use a chlorine shock treatment or another chlorine product to raise chlorine levels until your generator can catch up.

Chlorine shock treatments temporarily raise free chlorine levels in a pool to very high amounts in order to kill off any active bacteria or algae in the water.

Because these levels will drop naturally as the chlorine is used up, this treatment is appropriate for rapid sanitation of a saltwater pool that cannot be achieved by the saltwater chlorine generator.

Please note that using calcium hypochlorite, also known as cal hypo, should be avoided in saltwater pools.

Although this type of shock is very common and widely recommended in many cases, using it in saltwater pools is associated with an increased likelihood of calcium scale developing.

Liquid chlorine (aka sodium chlorite) is recommended for shocking pools, as it doesn’t contain calcium and is unstabilised, meaning that it won’t lift your cyanuric acid level too high.

Bear in mind that many liquid chlorine products do not state their active chlorine concentration, so it can be difficult to calculate how much to dose.

Use a chlorine calculator to help you work out the approximate dose, and add fractions of this recommended dose in batches until your desired free chlorine level has been reached.

Read more in this guide on how to shock a salt water pool.

Conclusion

Saltwater pools actually do contain the same amount of chlorine as traditional chlorine pools.

In some rare scenarios where your chlorine generator is malfunctioning or your salt levels are too low and an algae outbreak has started, it is appropriate to temporarily add chlorine directly to a saltwater pool until the salt cell can catch up.

Do you have any questions about adding chlorine to saltwater pools? Let us know in the comment section, we’d love to help!