(Last Updated On: July 25, 2019)

I have been asked many times if chlorine is effective in killing fleas so I decided to write a post about it.

How To Use Chlorine In Your Washing To Kill Fleas

For simple removal, washing your flea infested clothes in regular temperature or cold water can do the trick. But if you’re looking for ways to also effectively get rid of the eggs and larvae that can find their way into your clothes, more rigid washing methods may be needed.

Related: My review on Simple Guard 3


Immerse clothes that can withstand bleach in a solution of bleach diluted with water. If you’re using a machine to wash your clothes, the ideal chlorine to water ratio is 1 cup for every 16 gallons of water. The chlorine will effectively kill fleas and their eggs along with disinfecting your infested clothes.

For heavy duty clothes, it can also be beneficial to wash them with the highest water setting, at the hottest temperature and the longest wash cycle that your washing machine offers. After going through this, fleas, eggs, and larvae stuck on your clothes will surely be killed and removed in the process.

Because not all clothes can withstand contact with bleach, antimicrobial detergents that have pine oil or other phenolic disinfectants can also do the job. One cup for top loading machines and only a half cup for front loading ones should be enough.

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If you’re wondering if you can take your flea infested pet to a swimming pool in the hopes of the chlorine in the pool killing the fleas, then it may not be a very effective idea. While straight chlorine can kill fleas, the safe amount of diluted chlorine in a pool may not be enough to get rid of the fleas on your pet. While there is a chance that the fleas may drown in the water, the chlorine content itself may not kill them and might not drastically reduce your pet’s infestation.


The best way to get rid of a flea infestation on your pet is to use products that are specially formulated for that purpose. There are pet shampoos and soaps that have chemicals that effectively kill fleas, eggs, and larvae that may be on your pet’s body. And there are also sprays that serve the purpose of killing and repelling these fleas from your pet.

If you’re worried about your pet catching fleas from another pet in a public swimming pool that allows pet swimming, then it’s a very likely risk that cannot be prevented by simply relying on the chlorine in the pool to kill the fleas before they can get to your pet. The best method to avoid getting infested both in and out of the pool is still to use a waterproof flea repellent. Chances are the fleas will transfer not by floating from one pet to the next, but by actual contact, so your pet is in no less risk at the pool than if they were to encounter another flea infested pet on a walk.

What If My Swimming Pool Has Fleas?

Most insects cannot survive in your pool water as long as it has a free chlorine level of 1.0ppm. If you find your pool infested with fleas, the best method to get rid of them is to skim the surface and do an initial shock treatment.

A shock treatment is also called super chlorinating and this is done to kill bacteria and other unwanted organisms in your pool water in order to keep it safe and clean. This method requires you to drastically increase the amount of chlorine in your pool in a short amount of time by adding three to five times the usual amount of chlorine or another chemical sanitized to your pool water.

This is a maintenance method that should regularly be done and that most pool owners should be familiar with. Once the initial shocking is done, maintaining the regular amount of chlorine in your pool should be enough to kill any organisms until it’s time for the next shocking treatment. Here are a few tips for shocking:

  • Shock your pool at least once a month. For warm pools, it’s better to do it at least twice a month. For more frequently used pools (like public pools) during hot weather, it’s highly recommended to do the shocking once per week.
  • Shocking must be done when the available chlorine and free available chlorine total are already below the recommended ranges.
  • Shock after sunset. This way, the UV rays from the sun will not be able to affect the chemicals used in the treatment.
  • When preparing the shock chemicals, they must be dissolved in a bucket of pool water first.
  • Never add water to the chemicals, instead, add the chemicals to the bucket of water.
  • Stir it well, pour carefully, and pour as close to the water’s surface as you can in front of a return line fitting.
  • Never get into the pool unless the chlorine levels have gone back down to 3ppm or less.