As the name suggests, fish tank chillers are designed to keep the water in your fish tank cool in warmer climates. They are mainly used in marine aquariums where fish tend to be highly sensitive to temperature although fancy goldfish in tropical climes also benefit from the use of a fish tank chiller. An additional benefit is that cooler water has a greater capacity to hold dissolved oxygen thus avoiding issues with low levels of oxygen in your aquarium.
When do you need the fish tank chiller?
A fish tank chiller will be required when you run an aquarium with fish that prefer to live in cold water only. Aquarium chillers will maintain the water temperature you desire. Changing the temperature is something you need to do yourself, manually.
An alternative to a chiller is to run an air conditioning unit in the room that contains the aquarium, however running the air conditioner just to keep the fish tank water at the desired temperature can be a very expensive option. And even though a fish tank chiller may seem like an expensive item it will soon pay for itself if you are not running the air conditioner day – especially if you are not home during the day or you are on vacation.
Another chiller alternative is to add ice to the tank but this is highly impractical unless it is a very short term method to deal with heat wave conditions. If you do need to add ice to your tank it can be added by freezing water in a bottle. The frozen water bottle can be lowered into the tank or hung on the side of the tank.
For very warm climates and for fish that naturally require cold water there is no real alternative other than a chiller unit. It is also possible to purchase an aquarium heater and chiller in one unit which can be used year round to maintain the water temperature in both summer and winter.
When choosing your chiller you will have a choice of thermoelectric, in-line or drop-in fish tank chiller.
Thermoelectric chillers are commonly used in small tanks of less than 60 gallon capacity. They are energy efficient and silent running and can be used in both salt and freshwater aquariums.
Drop-in chillers are commonly used in saltwater aquariums or reef set ups. They require no additional plumbing and are fitted in line with the tank filter. They are simple to install and have low maintenance requirements.
In-line aquarium chillers are manufactured for tanks with a capacity of 60 gallons or more. They have a motor, a compressor and cooling fans and will require a well-ventilated area for installation. They may require professional installation and they are quite large.
An aquarium thermometer is an inexpensive necessity to use in conjunction with your tank chiller. If your chiller fails or mismanages the temperature of your aquarium you need to know immediately. A thermometer is a reliable way of monitory the temperature.
The main disadvantages of fish tank chillers are the cost of the units themselves – which can vary from a few hundred up to several thousand dollars – and the energy that they consume, which can be 80-100 watts per hour.
By Alison Stevens
Alison Stevens is an online author and maintains The Goldfish Site and The Goldfish Blog to assist anyone who wants to get started with setting up an aquarium fish tank and keeping freshwater fish.