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Do Aquariums Need Carbon?

Carbon Good for Fish Aquariums San Diego, CA

The use of carbon in the fish keeping hobby is relatively new. While many bodies of water are exposed to carbon in the form of bituminous coal, which is a form of organic rock, the biochemical processes that carbon deposits generate in natural habitats aren’t necessary in fish tanks. They’re complementary, but they can also provide benefits that make fish keeping more efficient.

Unlike other important fish tank supplies, carbon isn’t something you’ll normally find as part of an aquarium starter kit. Incorporating it into your tank maintenance routines is a personal choice. A healthy aquatic ecosystem doesn’t hinge upon using carbon, but some of its properties make it ideal for some aquarists.

Understanding Activated Carbon

Granular carbon made with peat and other natural ingredients such as coconut and bamboo is called activated carbon, although some aquarium shops may sell it as activated charcoal. Activated carbon looks like dark pellets that are about the size of small substrate pebbles. You shouldn’t work with smaller or powdered carbon unless you use a special small micron filter bag made for it. In essence, carbon is a filtration element that can keep water clear and odor-free. Nitrobacter colonies can also adhere to carbon, which is why some biological filters contain this material.

How Activated Carbon Works

The reason activated carbon is used in the aquarist hobby is because of its absorbent properties. Invisible water contaminants such as tannin particles, which are released by decomposed proteins from fish food, eventually result in a yellow coloration, and this is one of the contaminants activated carbon can deal with. Carbolic acids caused by fish waste and other biological process cannot be seen, but they can certainly be smelled. With granulated carbon in the tank, these acids can be absorbed and filtered.

Liquid Carbon

This aquarium supplement, which is basically CO2 in a bottle (the C without the O2), shouldn’t be confused with activated carbon. Liquid carbon is a fertilizer that aquascaping enthusiasts use to make plants look their best. It’s important for fish keepers to know the difference between liquid CO2 and activated carbon so they don’t mistakenly use one in place of the other.

How to Use Activated Carbon

If you run into images of carbon satchels hanging from aquarium tank walls, you should know this is an incorrect way of using it. There are three ways activated carbon is sold: granulated in a container, as a sheet, or as a cube. Carbon should be a part of the filtration system. The effectiveness of carbon lasts no more than a couple of months. You shouldn’t let carbon granules or pellets disintegrate into powder because the fine particles may irritate the gills of some delicate fish. If you see dark grains floating in the water, you’ll know it’s time to either replace or remove the spent carbon.

To learn more about adding carbon to your tank or any other aspect of aquarium care, reach out to Aquatic Warehouse. We’ve got you covered with everything you need to properly maintain your aquatic environment, whether you need an aquarium temperature controller, beneficial bacteria, protein skimmers, testing kits, or any other supply. Stop by our store in Kearny Mesa, order your supplies from our website, or give one of our knowledgeable representatives a call at 858-467-9297.



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    San Diego, CA 92123
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