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How Long Does Activated Carbon (GAC) Last? 10 Things Must Know

How long does activated carbon (GAC) last? Generally, activated carbon lasts 2 to 4 weeks. The effectiveness of the carbon would depend on the water condition. The more dirty water, the more it will affect the carbon filter. You have to maintain the water quality to avoid the corals and microalgae from producing in the aquarium.

How long does activated carbon last

What is Activated Carbon?

Activated carbon is the bituminous charcoal, lignite, or wood treated at a high temperature to make it naturally stable. It changes its biology to become the dark black substance that works as the filter for the water. It would have tiny pores which act as the water filter.

Water passes through these tiny pores and kills the harmful bacteria.

Activated carbon looks like a sponge that consumes the water and filters the small particles. You can also deal with the bad odors and trace elements with the Activated carbons.

Every AC would have charged particles in it. If the activated carbon does not have to charge particles, it will not work efficiently. Also, always use the activated carbon made especially for the aquarium. A wide range of AC is available in the market, which makes it challenging to choose.

For aquariums, you need special bituminous charcoal with granular form. This type of activated charcoal is called granular activated charcoal or, in short, the GAC for short.

Does activated carbon expire?

Yes. When activated carbon used in the aquarium, the charge of the carbon reduces over time. Also, the carbon pores get reduced, blocking the water and other substances from passing through. The activated carbon doesn’t have a shelf life.

If it is never used and kept at a secure place in a close companion aware of the environment, it can last for longer. Activated carbon is known for its adsorption characteristics. Until the absorption characteristics of the AC is available, it will sustain for longer.

It would help if you kept it dry and separate it from the volatile organic chemicals.

Read How Long Does Water Take to Dechlorinate ? 7 ways

Can you clean and reuse activated carbon?

Yes. You can easily clean and reuse the activated carbon in your aquarium. It is widely used in the water filtration process. Many aquariums would have the activated carbon-based filtration process to remove the bad odor and kill the harmful bacteria.

However, you need to clean the activated carbon to keep it activated for a long period. As you start using it in the filtration process, the carbon pores get blocked with the substance found in the water.

Also, the algae, waste products, and food waste would occupy the carbon space and create a layer that stops the filter from working. Regular cleaning would help you to clean the activated carbon and remove any blockage from the AC.

Once the pores are clean, they start working as normal again. Activated carbons are good for keeping the toxin substance like chlorine and heavy metals away from the water. It blocks during the filtration process and keeps the fish in the aquarium in a safe zone.

You will observe that the water gets cleaner over time and the small substances vanish from the water. Also, the water smells good, and no bad odor problem would be seen, which is good for the fish’s health.

Naturally, it takes the activated carbon to stop working after three to four weeks. The depletion of the AC depends on the waste product available in the water. The worse the water condition, the more effort the AC has to put into cleaning the water. Some AC may not last long if they use the maximum time to clean the water.

It would help if you used it with the extension service as it is meant to keep aquarium water clean and odor-free

How do you get to know that Activated Carbon has stopped working?

The water filtration process would get reduced, and you will notice the water turning pale yellow over time. Also, the bad odor of the water would increase. Additionally, the water’s small particles would start appearing in the water flowing with the filter’s force. If you see the change in the water condition, it is a sign that the activated carbon has become dirty and it is not able to clean the water anymore.

It is time to clean the filter and get it in normal condition.

How To Clean Activated Carbon?

The activated carbon lasts as in the aquarium filter for several weeks if you manage the waste product in the tank. Cleaning is necessary every 30 days to keep it working all the time. The activated carbon gets jammed with the existing debris in the tank.

In the filtration equipment, the charcoal filter is an important part of the filter. It will start working fine when the charcoal is cleaned properly. The cleaning process is not challenging, though you have to learn how to clean them with the proper cleaning guideline.

Take some proper measures to ensure that the carbon is no damaged and it is fully secure.

Step-by-step guide to clean the Activated Carbon-based filter

Step 1: Remove the filter from the aquarium

Remove the filter’s electric connection before you put your hand in the water to remove the filter. Anything connected to the electricity should be switched off or removed from the main switch to avoid any electricity from flowing in the water. Once you have removed the switch, carefully remove the filter from the aquarium and keep it aside.

Step 2: Carry the filter to the cleaning area

After the filter is removed, move the filter to the basin or the bathtub. You have to pour the water forcefully on the filter to clean the blockage. Also, the dirt trapped in the water will not get removed by washing with the hand.

It would help if you had a flow of water that regular force to make the dirt taken down from the carbon filter’s pores. Spill the water with force in all the corners. Ensure that the water is applied directly to the carbon to easily remove the small particles trapped in the carbon.

Step 3: Open the filter to clean the charcoal

Open the filter gently; It would have charcoal in the casing. The component would be removable, so carefully remove it. Separate the filter and the charcoal from the filter to clean it.

Step 4: Clean the Charcoal

Put the charcoal in the warm water and submerge it entirely under the water. It will lose the trapped substance found in the top layer. Later rinse it under the running water for several minutes. Gently rub the hand on the charcoal to remove the algae’s top layer and give way to the water to go inside the pores.

When applied with force on the charcoal, the running water will eradicate extra residues from the charcoal body.

Step 5:Take out the activated carbon

Once the cleaning is done, take out the activated carbon. Hold it in your hand and take it to near your ear. Check if you can hear anything. The activated carbon produces cracks and crunching sounds when removed from the water. It shows that the GAC is still working and ready to use in the filter.

Put the carbon back place in the filter. If there is no sound in the carbon, it means the activated carbon is no longer working. You have to replace it with the new carbon component.

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How often should you replace activated carbon?

It is recommended to replace the activated carbon every 1 to 3 months. If you are using chemicals in the aquarium to keep the water clean, you should first remove the filter from the tank and then pour the chemicals. Let the fish become comfortable in the new freshwater.

If the fish find the new habitat comfortable, then put the GAC back in the aquarium. The activated carbon removes the medication from the water.

Before your chemicals get time mixed in the water, they will be consumed by the filter, and the effects of the chemicals to clean the water or improve the health of the fish cannot be experienced.

If your aquarium has plant-based aquascaping, then it is recommended that you not put the activated carbon-based filter in the tank. It will eat all the good substances that your plant needs to survive.

Can you reactivate activated carbon?

Yes. It is possible to reactivate the activated carbon if it has lost its power after using it for few months. You would require to go with the heating process. The carbon goes back to normal when it is heated up to 90 degrees celsius.

During the heating process, the activated carbon removes all the impurities that it has adsorbed during the filtration process. Remember that the impurities trapped in the carbon may become toxic, so you should have a proper arrangement to heat the activated carbon in an isolated place.

How to change activate carbon?

The activated carbon found in the aquarium gets clogged due to debris. The debris is flowing in the tank pass through the filter and the carbon pores where the large chunks are stuck, blocking the area. Therefore, cleaning the activated carbon-based filter regularly would keep it in good condition.

Even after cleaning the charcoal filter, the final option is to replace it with the new carbon filter if the activated carbon is no longer working. Replace it with a good quality filter bag as it may last longer and provide the necessary protection to the fish available in the aquarium.

Without replacing the non-working activated carbon, your aquarium would stop working. It is vital to change the activated carbon when it loses its functional ability. Replacement is necessary to keep the water clean and breathable to the fish.

The health of the fish will stay intact if the water condition is good. The activated carbon ensures that the water quality stays in balance and provides a nice smell. Without the activated carbon-based filter, the water would smell bad, and you will have a bad odor in the home.

Final Verdict:

The activated carbon-based filter is highly recommended to keep your fish in good health. It saves you lots of time and money that you may have to put in the managing water condition. Use the above guide when it comes to replacing or cleaning the activated carbon.

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About Dr.Chamika

Hello, I'm Dr. Chamika. I am a Researcher in Water quality, Aquatic organisms, and Environmental chemistry. I am a passionate fish keeper, with10 years of experience. My mission is to help other aquarists experience the joy of fish keeping.