Heating 10 watt temperature adjustable USB

Heaters are one of the most overlooked devices in this hobby. They are the leading cause of tank crashes and the loss of an entire tank of expensive, prized fish. This is very unfortunate because they are actually one of the most affordable devices and something we have the most control over.

The problems with aquarium heaters are:

• They are often FAR too big for the tanks they are recommended for, over 0.5 to 1 watt per litre.
• They often fail
• They usually fail in the “on” mode and literally cook the fish in the aquarium
• They have no built-in redundancy

There are constantly sad situations on social media where the heater in an aquarium was left on and all the fish in an aquarium boiled. In many situations, the temperature rose to the point where the owner could no longer touch the water. That’s seriously overwhelmed heating.

The electric current to the heater is controlled by a thermostat, a mechanical contact that allows an electric current to flow. This thermostat turns “on” and allows current to flow and then turns “off” and cools down. That contact will often melt shut in the “on” position, preventing the power from being turned off. Electronic controllers use a different approach, but they too can fail.

Looking at size recommendations for a heater, most heater manufacturers use 2.5 watts per litre. This maximises the manufacturer’s profits. And everyone and their uncle will repeat this recommendation over and over again on social media. And aquarium equipment suppliers love it. 2.5 watts per litre is a VERY dangerous recommendation. 2.5 watts of power per litre can raise the temperature of the water by 17 to 28 degrees Celsius and cook the fish if the heater is stuck in the “on” position. Any heater that can do this is obviously very big.

The “basic rule” should be:

When it comes to aquarium heaters, redundancy is essential with a total maximum wattage of 0.5 to 1 watt per 1 litre.

The easy way to achieve redundancy is to use two smaller heaters. Whereas a faulty 100-watt heater can bring a 75-litre aquarium to a killer 41°C, a faulty 50-watt heater (of the two) can only go to 32°C, saving the fish. It would be highly unusual for two heaters to stay on at the same time.

The best situation is two low wattage heaters for most aquariums in homes. If one has the normal aquarium in a room at 21°C and one wants to keep the aquarium at 25°C, the following is recommended:

The reason the level goes from 0.5 watts per litre with 400 litres to 1 watt per litre with the 10-litre aquarium has to do with the ratio of surface area (all six sides) to volume. The smaller aquarium has a higher ratio and therefore generally needs more wattage. And we know some wattages are not commonly available, but try to get as close to the wattage total as possible.

The two heating elements should be set to different temperatures. One should be set to, say, 25°C, while the other can be set to 23°C. This prevents frequent on/off cycles of the heaters causing them to wear out.

If the room temperature regularly drops to 18°C and you want to maintain 27°C at all times, these wattages should roughly double and you would have to go with three heaters. That said, there is no reason to maintain 27°C at all times. If the temperature drops even to 18°C, no tropical fish has been found to die at that temperature.

And all electrical equipment in a tank adds heat. A 45-watt submerged pump adds 45 watts of heating 24 hours a day, seven days a week. A 50-watt pot filter is like a 20-watt heater on 24/7, if the pump motor is on the outside of the pot filter. Even circulating powerheads can add five or 10 watts of heat. And a 15-watt LED light fixture will bring most of that wattage into the tank as light that is then converted into heat in the aquarium. A 36-watt UV lamp heats up the water quite a bit. So something like this should be taken into account and the heating requirements adjusted downwards.