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The Gravel Vacuum

Cleaning Your Aquarium Gravel

(The First Tank Guide)

What is a Gravel Vacuum?

Most aquarium gravel vacuums (sometimes called a gravel vac or an aquarium vacuum) consist of a clear, wide, rigid, plastic tube, typically about 2" in diameter, attached to a narrower, flexible, siphon tube, typically about 1/2" in diameter.

A gravel vacuum uses the action of the water flowing through the siphon (and through the gravel to get into the siphon) to loosen debris from the gravel and remove that debris and solid waste from your fish tank.

This is an important part of your routine aquarium maintenance as it removes this decaying debris from the tank and clears the channels through the gravel, making your under gravel filter more efficient (if you are using one) and preventing the development of anaerobic pockets in the aquarium gravel. If these anaerobic pockets develop, they can release toxins into the aquarium water, which can harm or kill your fish or biological fiter.

Picking the Right Gravel Vacuum

The wide part of the tube (the vacuum) should be almost, but not quite, as tall as your tank is, as this will make operation of the gravel vac much easier. If the wide part of the tube is much shorter than the tank, then it will be more difficult to keep from vacuuming up gravel when you're doing your water changes. If it is too tall, it makes it harder to get the siphon started, and to control the vacuum once the siphon is started.

The narrower siphon tube will need to be 4-6' long to make it easy for you to reach the bucket with the other end of the tube, and allow you to move the gravel vacuum around the tank as necessary.

Usually both the siphon tube and the gravel vacuum attachment are sold together as a single unit, but some are sold separately. It really doesn't matter which you choose.

What Are Gravel Vacuums For?

Gravel vacuums are used when performing your regular weekly 10-15% water change to clean part of the gravel while removing the water. This is important in all aquariums, but is particularly important in an aquarium with an under gravel filter.

Are There Automated Gravel Vacuums?

Some manufacturers produce a gravel vacuum that can be attached to a faucet. These gravel vacuums allow you to remove water from the tank while cleaning the gravel, then to fill the tank again without using a bucket or having to start a siphon. Though cleaning the gravel is the same with one of these devices as it is with a regular gravel vacuum, you will need to consult the manufacturer's instructions for attaching the apparatus to your faucet and for switching from drain mode to fill mode. If you are using one of these, remember to add dechlorinator to your tank prior to adding new tap water to minimize the exposure of your fish, plants, and biological filtration to toxic chlorine.

"Great website-very thorough!"
August 31, 2007
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"Thanks for the quick response Keith! [...] I appreciate your advice and your website! Thanks!!"
October 14, 2006
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