How Do Aquarium Ice Probes Work?

An aquarium ice probe is a type of aquarium water chiller. It cools the aquarium water, maintaining the low temperatures that are necessary for subtropical and temperate species of aquatic wildlife to thrive. The ice probe is a solid-state thermoelectric cooler that uses principles discovered by French physicist Jean Peltier. The device uses a special kind of conductor located on its interior that creates a very cold surface that chills the water in direct contact with it.

  1. Peltier Effect

    • When electricity flows through a circuit made with two dissimilar conducting materials, such as a nonconductive ceramic substrate and a metal conductor plate, the nonconductor absorbs heat and the conductor reflects or emits heat. Thermoelectric modules, such as the ice probe, are heat pumps that utilize this effect with electrical wires to a series of paired positive and negative semiconductors made from bismuth telluride. These semiconductors are enclosed by a conductor on one side and a nonconductive material on the other side.

    Ice Probe

    • The ice probe must be plugged into an external AC-to-DC converter that plugs into an electrical outlet in order for its special thermoelectric circuit to work. The ice probe works by pulling heat out of the tank water and radiating it out into the air with a low-speed fan. Unlike air conditioners and refrigerators, an ice probe does not require a compressor that utilizes coolants or refrigerants such as Freon to cool the air. Instead, it removes heat from the water and dissipates it with the use of a heat sink and a fan.

    Safety Features

    • The ice probe fan moves hot air away from the heat sink, which is the conductive side of the thermoelectric module in the ice probe, to prevent it from overheating and starting a fire. If it does become too hot, the internal thermal switch, called a safety thermal fuse, turns the ice probe off and will turn it back on once the heat sink has cooled to normal operating temperature. To allow the ice probe to work more efficiently and not overheat, install it in an area where there can be 4 inches to 6 inches of open air space around the chiller fan to allow for proper heat ventilation.

    Uses

    • An ice probe will cool 10-gallon to 20-gallon aquariums. It can also cool insulated bait tanks and specimen tanks. The ice probe can cool 10 gallons of water by 6 degrees Fahrenheit to 8 degrees Fahrenheit below room temperature. A single ice probe can chill 20 gallons of water by 3 degrees Fahrenheit to 4 degrees Fahrenheit and 40 gallons of water by 1 to 2 degrees Fahrenheit. Two ice probes can chill 10 gallons of water by 10 to 12 degrees Fahrenheit, 20 gallons of water by 6 to 8 degrees Fahrenheit and 40 gallons of water by 3 to 4 degrees Fahrenheit. Or, in a fully insulated 10 gallon aquarium, a single ice probe can chill the water by 20 degrees Fahrenheit.