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Aquarium Chillers

What Is a Chiller and Why Might I Want One for My Aquarium?

(The First Tank Guide)

A chiller is a piece of aquarium equipment used to keep the fish tank water cool - or, rather, to keep the fish tank from rising above a particular temperature.

What Is an Aquarium Chiller?

An aquarium chiller is really a small refrigerator which is installed in-line with an external filtration system to cool - or chill - the water as it passes through the system.

When coupled with a thermostat, the chiller can prevent the aquarium from rising above a per-determined temperature. This can be very important when keeping cold water fish like trout or bass, or when keeping temperate water species like goldfish in a warm climate.

While an aquarium heater will help keep the fish tank warm for tropical fish, a chiller keeps the aquarium cool.

Why Would I Want a Chiller on My Aquarium?

If you are keeping fish that need colder water and the higher dissolved oxygen that water provides, then keeping the water cool enough for these fish will be important.

A chiller will help you to maintain the cool water temperature that cold water fish require, thereby allowing you to keep these fish. This becomes more important the warmer your climate - or, more particularly, your home - is.

What Do I Need to Know About Aquarium Chillers?

Most aquarium keepers, particularly most beginning aquarium keepers, do not have any need for a chiller. Aquarium chillers really are for more advanced aquarium systems.

Chillers are generally designed for larger aquariums. In part, this is because most of the fish that require chillers are larger fish and they need the larger aquarium. Also, cold water fish tend to require more space per fish, so that also mandates a larger aquarium.

Chillers are also usually fairly expensive pieces of equipment - and probably aren't stocked by your local pet shops, since they are not often needed (generally because most people are not keeping the kinds of fish that usually require a chiller).

Where Can I Get a Chiller if I Need One?

If you are planning on keeping fish that will require a chiller, check with your local pet shops about what can be ordered, and what other equipment is necessary. Many chillers will require external plumbing, and almost all will require a pump with the correct flow rate for that chiller.

Before ordering any cold water fish, make sure your chiller is set up and operating correctly, and that your aquarium is maintaining a constant temperature.

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