
These aquarium heaters allow you to select a temperature within a defined range, generally between 66-96˚F (19-36˚C). But if you have a small fishbowl with less than 3 gallons of water, a compact preset heater will leave you with more space for your critters or decorations.įor the rest of you? The next aquarium heater is the only one you should consider… 2. I generally don’t recommend “always-on” preset heaters. Without the need for a thermostat, manufacturers have been able to create some impossibly slim and small aquarium heaters. The number one advantage of preset heaters is their size. This nifty device shuts your heater off if your water becomes too hot and turns it back on once the water cools – keeping your fish safe. However, you can get around this with the use of an aquarium temperature controller. If the temperature of your room increases, say on a hot summer day, then using these heaters will also increase the temperature of your tank – which may be too hot for your fish. You don’t have to go far to find horror stories of preset heaters killing fish.Īlways-on heaters don’t regulate the temperature. However, the majority of the preset heaters designed specifically for small tanks operate a little differently – they are “always on” and never shut off.ĭo you have fish that prefer cooler or warmer water? Tough luck! You cannot change it – you are at the mercy of your heater. Once this temperature is reached, the heater automatically shuts off and won’t turn on again until the temperature drops. Ordinarily, preset heaters have been manufactured to reach a specific temperature – typically 78˚F (26˚C). Types of small aquarium heatersįirst, let’s cover the two different types of heaters you can choose from… 1. If your heater cannot warm your tank within 7 hours, it’s probably too small. The following table shows the heater wattage you need in order to heat a tank up to 10˚F higher than your room temperature. The bigger your aquarium, the more watts you need to heat it.

A 20-watt heater, for example, is twice as powerful as a 10-watt one. The more watts, the more powerful the heater. The power of an aquarium heater is measured in watts (W).

The temperature you want to raise your aquarium water to.The following three conditions determine the correct-sized heater for you: More often than not, the problem is that they are using the wrong-sized heater for their tank. Want the answer? Read on! The limitations of small aquarium heatersīy far, the most common complaint I hear about small aquarium heaters is… Best small aquarium heater for 6 to 10-gallon tanks.Best small aquarium heater for 2.6 to 5-gallon tanks.Best small heater for 1 to 2.5-gallon tanks.The limitations of small aquarium heaters.Which heater is best for your tiny tank?.
