How Long Does It Take For Chlorine To Evaporate From Tap Water

Chlorine is one of the most common elements in tap water. It is essential to get rid of this chlorine element in the tap water before introducing it to the fish tank. Evaporation is one of the most effective ways of getting rid of chlorine from tap water.

How Long Does It Take For Chlorine To Evaporate From Tap Water?

Typically it will take between 24 to 72 hours for the evaporation of chlorine from tap water takes , depending on the quantity of water. You can accelerate the evaporation process by increasing the temperature, exposing the water to to UV light, and aeration.

How Long Does It Take For Chlorine To Evaporate From Tap Water

It is estimated that it would take about 110 hours for 2 ppm of chlorine to evaporate from 10 gallons of standing tap water. However, boiling the water will reduce the time to about 6 to 8 minutes.

It is more difficult for marine fish to cope with high chlorine levels compared to freshwater fish. Also, fish that prefers an alkaline environment will have a hard time coping with high chlorine content.

Aquarists usually explore several methods to remove the chlorine compound in tap water because it is not safe for the tank members. They usually seek the most efficient, affordable, and effective method.

What Are Other Ways of Getting Rid of Chlorine from Tap Water

Aquarists often seek ways to get rid of chlorine from tap water to make it suitable for fish aquariums. Evaporation usually takes a long time; therefore, there is a need to check out other alternative means.

Most of these alternatives are usually faster and efficient. Other ways of getting rid of chlorine from tap water include; aerating the tank with an air pump, using a carbon filter, adding ascorbic acid, boiling, and exposing the water to UV light.

Using Boiling Method to Get Rid Of Chlorine from Tap Water

Boiling is one of the fastest and most effective ways of eliminating chlorine from tap water. Boiling works by creating enough heat to increase the movement and aeration of water. This process helps in the elimination of the volatile chlorine present in the water.

Also, boiling reduces the ability of water to hold dissolved gasses. Hence, heating will reduce the probability of water holding chlorine gas. It is estimated that it only takes 6 to 8 minutes for the boiling method to remove 2 ppm of chlorine from 10 gallons of water.

However, the limitation of this method is that it is not suitable for a large quantity of water. If you have a large quantity of water to boil, you might have to boil it in batches.

Using Ascorbic Acid to Remove Chlorine from Tap Water

Ascorbic acid is an effective way of getting rid of chlorine in the tank because it naturally neutralizes chlorine. This method is affordable and efficient. It is also easy to carry out.

Ascorbic acid will not dissolve in water; instead, it will precipitate chlorine out on the water’s surface. This method is easy to use and economical. It is economical because you don’t need a large quantity of ascorbic acid before it works.

1 tablespoon of ascorbic acid is enough to eliminate the chlorine content in 1 gallon of water. This calculation means you only need 10 tablespoons of ascorbic acid for 10 gallons of water.

The good news about the use of ascorbic acid is that it gets rid of both chlorine and chloramine. Also, the use of ascorbic acid is beneficial to both plants and other life forms in the tank. The reason is because it performs this elimination without depleting the amount of oxygen.

Using UV Light to Remove Chlorine from Tap Water

The ultraviolet ray has a lot of importance to human existence. It is particularly useful for aquarists that want to get rid of chlorine from tap water. However, the process might be relatively expensive because you need a UV light source.

The level of UV light you will need is dependent on the quantity of water you intend to treat. It would be best if you had UV rays with a wavelength of 254 nanometers or more. Also, the UV light’s energy density should be about 600 millimeters per 1 square cm of water.

Just like ascorbic acid, the UV light will also assist you to eliminate both chlorine and chloramine. The time required to dechlorinate your tap water with UV light is dependent on the quantity of water and the number of organic matter that it contains.

Removing Chlorine from Tap Water with Carbon Filter

First off, you should be aware that carbon filters can eliminate both chlorine and chloramine. It does this elimination while also providing clean and portable water for your aquarium.

The carbon filter activates some special carbon that can absorb and get rid of organic compounds and matter. It also eliminates chemicals like chlorine alongside.

However, it is essential to check the pH before adding a carbon filter to ensure it is safe.

Using Air Pump to Eliminate Chlorine in Fish Tank

Air pump aerates water to eliminate chlorine. The aeration will help in dechlorination by creating a perfect condition for the evaporation of chlorine. It will also improve water circulation that would, in turn, aid the evaporation of chlorine.

The time of aeration, type, and size of the pump is dependent on the quantity of water.


Chlorine is often undesirable in an aquarium, especially when it is present in high quantities. Therefore, it is essential to use a suitable method to get rid of chlorine from a fish tank.

Regardless of the method you are using; it is essential to get and use a chlorine test kit. This kit will help you to determine the chlorine level of the tank accurately. This knowledge is vital in determining if the chlorine level is safe for your fish or not.

Similarly, it is best to use methods that will eliminate both chlorine and chloramine. It would help if you didn’t overlook chloramine in water because it is also detrimental to fish’s health. Therefore, you can save yourself the stress of using a separate method for eliminating chloramine.




Hello, I'm Jason. I'm the guy behind I volunteer at my local fish shop and I created this site to offer tips and advice on the fish I care for.