Do Fish Tank Heaters Raise Electric Bill – How Much Money

In this article, we’ll take a look at exactly how much power and electricity your aquarium heater uses every day and also explore how much it will cost you each year to run your aquarium heater.

Our Top Rated Aquarium Heaters

Here is what you’ll learn;

Feel free to also check out our guide on how to use an aquarium heater where we answer many more questions and walk you through the installation and setup of your aquarium heater.

How Many Watts Are Used By An Aquarium Heater

Aquarium heaters use between 25-250 Watts and will use between 219-2019 kWh per year depending on the size of the heater you are using.

What Size Heater Do You Need For Your Fish Tank (Watts)

You can use the fish tank heater size chart below to help you determine what size of an aquarium heater (Wattage) you need for the size of your tank in gallons or liters.

The chart below will also show you how many Watts your aquarium heater will use, how much energy it will use each year and how much it will cost you.

Aquarium Heater Size Chart

Tank SizeWattsKwH (Annual)(USD) Yearly CostUK (EUR) Yearly Cost
5 Gallons/20 Liter2521930.6648.18
10 Gallons/40 Liter5043861.3296.36
20 Gallons/75 Liter5043861.3296.36
25 Gallons/100 Liter7565791.98144.54
40 Gallons/150 Liter100876122.64192.72
50 Gallons/200 Liter1501314183.96289.08
65 Gallons/250 Liter2001752245.28385.44
75 Gallons/300 Liter2502190306.6481.8

Further Reading: Best aquarium heater for a 10 gallon tank

Fish Tank Heater Energy Consumption (Annually)

To Find out how much power/energy your fish tank heater will use each year, you can use the following formula (or look at the chart above)

Multiply the total watts by the total number of hours the heater will be running per day, multiply that by 365 days for the year. Then divide the answer by 1000 to get the kWh

For example:

Filter (25 Watts × 24 hours/day × 365 days/year) ÷ 1000 = 219kWh

Fish Tank Heater Electricity Cost Calculator (UK & US)

To determine how much it will cost to run your fish tank heater all year, you can use the following formula to calculate the cost (or look at the chart above)

Take kWh for the size of your heater and multiply that by your electrical provider’s kWh rate.

For example:

If the average US kWh rate is 14 cents, then it would cost $30.66 to run a 25W aquarium heater all year long.

$0.14 * 219 = $30.66

Here is a very helpful resource that they update monthly on electricity rates broken down by every state.

Do Fish Tank Heaters Use A Lot Of Electricity

Compared to other appliances used in your house, fish tank heaters use a lot of electricity, considering how small they are.

To compare:

A standard fridge uses about 2.4 kWh each day. Where a 50W fish tank heater uses about 1.2 kWh each day.

So if you happened to be using two small 50W heaters, it would use as much power as your fridge!

That being said, the overall cost to run a 50W fish tank heater for the entire year is just over $60.00 or $5 each month.

In the end, it’s all relative.

Do Fish Tank Heaters Raise Your Electricity Bill

Yes, using a fish tank heater will raise your electricity bill each month. However, the total cost is minimal when you break it down to a monthly cost.

In the example above, a 50Watt fish tank, the heater would only cost $61.32 (USD) for the entire year and only $5.11 (USD) each month.

At the end of the day, I hope the cost of a fish tank heater doesn’t prevent you from getting into the hobby; it’s a great one!

Understanding the Impact on Energy Costs

Fish tanks are not just glass boxes filled with water; they are delicate ecosystems that require meticulous care and attention. One crucial aspect of maintaining a healthy aquatic environment is maintaining proper water temperature. For tropical fish and other aquatic creatures, maintaining a consistent and suitable water temperature is vital for their well-being. In this regard, electric heaters play a crucial role in ensuring that the water remains at a constant temperature. However, many aquarium owners often raise concerns about whether these heaters significantly impact their electric bill.

Understanding the Basics

A. The Significance of Water Temperature for Tropical Fish

Before delving into the intricacies of electric heaters and energy costs, it’s essential to understand why maintaining the right water temperature is so critical for tropical fish. These species are highly sensitive to temperature fluctuations. Maintaining the correct water temperature is essential for their health and well-being.

B. Types of Fish Tank Heaters Available

There are several types of fish tank heaters on the market, such as watt heaterssmall heaters, and even space heaters for very large aquariums. Each type has its unique characteristics and power requirements. Understanding these differences can help you make informed decisions about which heater is best for your aquarium.

C. Power Consumption and Its Relation to Heating Elements

The power consumption of a fish tank heater is a primary concern when it comes to your electric bill. The heating element’s wattage and the time it operates directly impact your energy usage and costs. Therefore, it’s crucial to comprehend the relationship between power consumption and heating elements.

D. Temperature Settings and Maintaining a Constant Temperature

Maintaining a constant temperature in your aquarium is not just about setting your heater to a specific degree in degrees Fahrenheit. It involves understanding how to balance the heater’s operation to achieve the desired water temperature consistently.

Assessing Energy Usage

A. Calculating the Energy Usage of Fish Tank Heaters

To determine how much your fish tank heaters impact your electric bill, you can calculate their energy usage in kilowatt hours. This calculation provides insights into the actual cost of heating your aquarium water.

B. Comparing Energy Costs During Different Seasons

Your electric bill may vary throughout the year, with higher costs during the winter months when you need to keep your aquarium water warmer and potentially lower costs during the summer months when less heating is required. Understanding these fluctuations helps you plan and budget for your aquarium’s energy consumption.

C. Factoring in the Impact of Ambient Room Temperature and Insulation

The ambient room temperature can affect how hard your heaters need to work to maintain the desired water temperature. Proper insulation and heat reflectors can help improve energy efficiency.

D. Comparing Different Heating Options

Consider comparing the costs and energy usage of electric heaters to alternative heating methods, such as gas heat, to make informed decisions about how to balance energy costs.

Practical Tips for Lowering Energy Costs

A. The Role of Proper Insulation, Heat Reflectors, and Small Changes in Settings

Small changes, such as adjusting the temperature settings slightly and using insulation or heat reflectors, can make a huge difference in your electric bill while still maintaining a safe and comfortable environment for your fish.

B. Energy-Efficient Equipment

Investing in energy-efficient equipment, such as watt lights and LED lighting, can help reduce energy costs in the long run.

C. The Potential of Solar Panels

Consider solar panels as a sustainable way to offset your aquarium’s electricity costs, especially if you have a large aquarium.

D. Understanding the True Cost of Maintaining a Fish Tank

It’s essential to understand the true cost of owning an aquarium, factoring in not only energy costs but also equipment, maintenance, and the well-being of your aquatic inhabitants.

Case Studies

A. Analyzing the Electricity Rate and Power Bill of Aquarium Owners

Real-life examples of aquarium owners and their power bills can provide insights into the actual costs associated with fish tank heaters.

B. Examining the Running Cost of Large Aquariums

Large aquariums with high power consumption can significantly impact your electric bill. It’s essential to consider these costs when planning your aquarium setup.

C. Comparing the Costs of Heating Water for Freshwater Tanks and Saltwater Tanks

Different types of tanks may have varying heating requirements and, consequently, different energy usage and costs.

Environmental Considerations

A. The Environmental Impact of High Energy Use in Aquariums

High energy use in aquariums can have a significant environmental impact. Exploring more sustainable heating methods, such as heat pumps or waste heat, can be beneficial.

B. Exploring Alternative Heating Methods

Alternative heating methods, like electric pond heaters, are worth considering, especially for outdoor tanks, as they can be more energy-efficient.

C. The Potential Benefits of Electric Pond Heaters

Electric pond heaters, in particular, can provide a turtle’s habitat with the necessary warmth while being mindful of energy consumption.


In conclusion, maintaining the right water temperature for your fish tank is crucial for the health of your aquatic life. While electric heaters are essential for achieving this, it’s equally important to understand their impact on your electric bill. By making informed decisions about the type of heater, energy-efficient equipment, and small changes in settings, you can effectively balance the well-being of your fish and live plants with your energy costs. Ultimately, taking steps to manage and reduce your aquarium’s energy usage can have a positive long-term effect on your budget and the environment. So, next time you set up your fish tank, consider the true cost of maintaining it, and make choices that are both economically and ecologically responsible.

Jack Dempsey
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