How Much Does It Cost To Run An Aquarium? (more than you thought!)

If you are looking to buy a new fish tank, or you have an existing aquarium, you may be wondering how much it costs to run an aquarium. You may be surprised by the results.

Eating Daphnia
Eating Daphnia

In this article, I am only focusing on the cost of electricity, and not so much on the cost of other expenses such as water, food, and consumables like filter media.

The cost to run an aquarium will vary depending on a large number of factors including the size of the aquarium, what filtration you use, what lighting you have, and how hot or cold your room is.

There are many factors to consider when working out how much power your aquarium consumes. In this article, I take a look at some of the major components and their electricity consumption to help you figure out how much power your aquarium is using.

Note: In researching this article I have had to make a number of assumptions. As every situation is different, the figures here are only provided as a rough guide. The number of variables is almost infinite. At the time of writing (March 2021) the average cost per kWh was 13.19 cents. If you live in Alaska or Hawaii, the cost per kWh will be considerably more. In other states, it may be less. Throughout this article we also assume that a) we are talking about a freshwater aquarium set up and b) we are just using the standard, off the shelf equipment that most freshwater hobbyists own and use

Which Equipment In The Aquarium Consumes Power?

Just being a glass box filled with water, the aquarium itself doesn’t consume any power. It is only when we start adding equipment that the power usage begins. I have looked at each of the following for this article;

Filtration

There are a number of different ways we can filter our aquariums. Sponge filters, internal power filters, under gravel filters, hang-on-back filters, and canister filters to name just a few. Each type of filtration will use a different amount of power. Sponge filters will consume very little power whilst a large canister filter may use a lot more.

Under normal conditions, a filter will run all day every day. For my calculations, I have assumed this is the case for all types of filters.



Hang-On-Back Filters

Hang-on-back filters are incredibly popular. They use a powered motor, which turns an impeller. As the impeller turns, it draws water up from the aquarium into the hang-on-back filter. Once the water is in the filter it passes through a number of chambers, each of which contains filter media. The water then overflows back into the aquarium.



The larger the hang-on-back filter, the more power the motor consumes to draw water up and through the media chambers.

In the table below I look at some of the most popular brands on the market.

FilterManufacturerAquarium Size (max)Power Consumption (watts)Cost to run for 1 month
C2Fluval30 US Gal (115 L)5w$0.47
C3Fluval50 US Gal (190 L)5w$0.47
C4Fluval70 US Gal (265 L)5w$0.47
Penguin 75Marineland10 US Gal (38 L)4w$0.38
Penguin 100Marineland20 US Gal (76 L)14.4w$1.37
Penguin 150Marineland30 US Gal (113 L)14.4w$1.37
Penguin 200Marineland50 US Gal (180 L)20.4w$1.94
Penguin 250Marineland75 US Gal (283 L)5w$0.47
AquaClear 20AquaClear20 US Gal (76 L)5w$0.47
AquaClear 30AquaClear30 US Gal (113 L)5w$0.47
AquaClear 50AquaClear50 US Gal (189 L)5w$0.47
AquaClear 70AquaClear70 US Gal (264 L)5w$0.47
AquaClear 110AquaClear110 US Gal (416 L)5w$0.47

From the table above we can see that both the AquaClear and Fluval Hang on Back Filters only cost an average of about $0.47 per month to run. This gives us an annual cost to filter one aquarium with these filters of just $5.64.

Canister Filters

Canister filters are also an extremely popular way to filter our aquariums. Typically we use canister filters either for larger aquariums or when we have messier fish like Goldfish or African Cichlids.

Much like hang-on-back filters, there are a number of different brands on the market and a number of different sizes, allowing canister filters to filter aquariums upto 400 US Gal.

The added benefit of canister filters is they allow us to modify the way we filter our aquariums by changing the media in the canisters.



As you may expect, the larger the canister filter, the more power they consume whilst pumping water through them.

In the table below, I look at some of the most popular canister filters currently on the market to see how much power they consume.

FilterManufacturerAquarium Size (max)Power Consumption (watts)Cost to run for 1 month
Fluval 107Fluval30 US Gal (115 L)10w$0.95
Fluval 207Fluval45 US Gal (170 L)10w$0.95
Fluval 307Fluval70 US Gal (256 L)16w$1.52
Fluval 407Fluval100 US Gal (378 L)23w$2.18
FX4 Fluval 250 US Gal (1000 L)30w$2.85
FX6 Fluval 400 US Gal (1500 L)41w$3.89
HW 302Sunsun75 US Gal (238 L)18w$1.71
HW 303Sunsun100 US Gal (378 L)35w$3.32
HW 304Sunsun200 US Gal (757 L)55w$5.22
BioMaster 250 Oase70 US Gal (256 L)15w$1.42
BioMaster 350Oase90 US Gal (340 L)16w$1.52
BioMaster 600Oase160 US Gal (605 L)23w$2.18
BioMaster 850Oase250 US Gal (946 L)25w$2.37

Using the information in the table above we can see that running a small canister filter like the Fluval 107 would only cost around $0.95 per month to run, which is around $11.40 a year. On the other hand, If you are running a large, powerful canister filter like Sunsun 304, the cost would be closer to $5.22 per month, which is $62.64 a year.

Sponge Filters/Under Gravel Filters

Unlike hang-on-back filters or canister filters, sponge filters and under gravel filters use air to power them. Rather than a motor drawing water into the filter and then passing through the filter media, they rely on air rising through the water column, drawing water with it.

This motion causes water to be drawn into the sponge, on a sponge filter, or down through the gravel and up an uplift tube in the case of under gravel filters.

With both sponge filters and under gravel filters, an air pump is required. The size of the air pump will depend on what you are asking it to do. If you have a single tank with a single sponge filter, a relatively small air pump will do the job.

If on the other hand you have an entire fish room with multiple tanks, each running more than one sponge filter, you will need a much larger air pump.

In the table below I compare some of the most popular aquarium air pumps on the market to see which ones use the most power.

Air PumpManufacturerAquarium Size (max)Power Consumption (watts)Cost to run for 1 month
Whisper 10Tetra10 US Gal (38 L)2.5w$0.24
Whisper 20 Tetra 20 US Gal (76 L)2.5w$0.24
Whisper 40 Tetra 40 US Gal (152 L)2.9w$0.28
Whisper 60 Tetra 60 US Gal (227 L)4.0w$0.38
Whisper 100Tetra100 US Gal (378 L)4.8w$0.46
AP20Aquatop20 US Gal (76 L)2.0w$0.19
AP30Aquatop40 US Gal (156 L)3.0w$0.28
AP40Aquatop50 US Gal (189 L)3.5w$0.33
AP50Aquatop60 US Gal (189 L)3.5w$0.33
AP100Aquatop100 US Gal (378 L)4.0w$0.38

Conclusion On Filters

From the 3 tables above, we can see that using sponge filters is the cheapest way to filter an individual aquarium. The next cheapest way is with a hang-on-back filter, followed by a canister filter.

Until I brought these figures together, I had not appreciated the difference in cost of running one canister filter compared to another. If for instance you wanted to filter a 200 gallon (757 L) aquarium using a Sunsun rather than a Fluval FX4, over a 3 year period, you would spend an extra $85 using the Sunsun!

I recently wrote an article titled Are Fluval Filters Good? which you might find interesting.

Lighting

I don’t think there is any other part of our hobby that has advanced as much over the years as lighting. When I started keeping fish, we used T12 bulbs connected to control ballasts. You would turn the light on and it took a while to warm up. Plus, you had to change the tubes on a regular basis otherwise the color faded.

Today we have access to ultra thin LED strips. These LEDs can be controlled by apps on our phones, you can change the color output to suit your individual aquarium and you can even simulate different weather conditions. The top of the range LED light fittings are now waterproof.

Lighting has come an awful long way in 30 years!



Almost all the fittings we buy for our aquariums today are going to be LED. In the table below I have only looked at different LED fittings available on the market. If you are running T5, T8, or even T12 bulbs still, the cost is going to be considerably higher than those listed below. For my calculations, I have assumed the light is on for 10 hours a day, every day.

As a side note, if you don’t have your aquarium light on a timer, get one ASAP. Having your lights on a schedule of the same ‘day length’ every day is a major part of winning the battle against algae.

ModelManufacturerAquarium SizePower Consumption (watts)Cost to run for 1 month
Plant 3.0 14520Fluval15- 24″ (38 – 61 cm)22w$0.88
Plant 3.0 14521Fluval24 – 34″ (61 – 85 cm)32w$1.28
Plant 3.0 14522Fluval36 – 48″ (91 – 122 cm)46w$1.85
Plant 3.0 14523Fluval48 – 60″ (122 – 153 cm)59w$2.37
AquaSky 2.0 14532Fluval24 – 36″ (61 – 91 cm)18w$0.72
AquaSky 2.0 14532Fluval36 – 48″ (91 – 122 cm)27w$1.08
AquaSky 2.0 14532Fluval48 – 60″ (122 – 153 cm)35w$1.40
Stingray JL-16SFinnex20″ (50 cm)11w$0.44
Stingray JL-24SFinnex24″ (60 cm)13w$0.52
Stingray JL-30SFinnex30″ (76 cm)16w$0.64
Stingray JL-66SFinnex36″ (91 cm)20w$0.80
Stingray JL-40SFinnex48″ (122 cm)27w$1.08

Conclusion On Lighting

The table above looks at 3 of the most popular LED aquarium lights on the market today. There are countless others available, not to mention the high-end options like Kessil lights which could be 40w each (and you would want several of them on a larger aquarium).

Out of the main pieces of equipment we run with our aquariums, lighting is one of the cheapest items. For many of us, it costs less than $10 a year to light an aquarium. Unlike with canister filters, there isn’t a great deal of variation in the running cost between brands.

Lighting is the one area where we can increase or decrease our costs by adjusting the number of hours of light the tank receives. Unlike a filter, which must run 24 hours a day, and a heater, which runs as and when required, lighting is completely controllable.

Depending on your aquarium setup, you may have 2 or even more lights running on an individual tank. If you do have more than one light, the costs will increase accordingly.

My article about does Fluval Aquasky grow plants might be worth a read.



Heating

Heating is often the most expensive aspect of running an aquarium. Aquarium heaters typically come in 50w, 100w, 200w, or 300w. There are smaller and larger models on the market, but these are usually for very small or very large aquariums.

It is extremely common in the hobby to use multiple heaters to achieve the desired water temperature. I myself currently run a 155 gallon tank which uses two 200w heaters rather than a single 400w heater.

When sizing an aquarium heater, there are two variables that need to be considered. Firstly, the size of the aquarium and secondly the number of °F above room temperature the water temperature needs to be increased by.

For instance, a 75-gallon tank that needs to be heated by 5°F above the room temperature would want a 200w heater, whereas the same tank that needs to be heated 15°F above the room temperature would require a 300w heater.

Where heaters vary to other equipment in the hobby is the amount of power consumed doesn’t vary by manufacturer. A 300w heater uses around 300w, no matter which company makes it.

As every aquarium is different, so is almost every setting in which that aquarium is located in, and so the length of time a heater is running for will vary from tank to tank, and for that matter, month to month.

For the sake of comparison, I have estimated, on average, an aquarium heater will run for about 8 hours per day, all year round.

Heater SizeAquarium SizeCost to run for 1 month
50w10 US Gal (38 L)$1.60
100w30 US Gal (114 L)$3.21
150w55 US Gal (208 L)$4.81
200w75 US Gal (284 L)$6.22
300w90 US Gal (341 L)$9.63

Running an aquarium heater can prove expensive, especially as so many of us quickly escalate from a single aquarium to multiple aquariums.

Heating a 90 gallon tank can cost over $100 a year. This is by far the most expensive piece of equipment most of us will run in our aquariums. To keep the cost of heating an aquarium down, there are several things we can do;

  • Insulation: Insulating either the room the aquarium is housed in, or the tank itself, is probably the best way to keep heating costs down. In the past, when I have housed aquariums in an unheated garage, I have surrounded each tank in polystyrene. This insulating layer reduced the heat loss and therefore reduced how long the heaters ran for.

  • Use the correct size heater: Sizing your aquarium heater correctly will have a big impact on the amount of power it consumes. A heater which is too small will be on for many more hours than the right size heater. Conversely, using a 300w heater in a 50 gallon aquarium will also just waste power.

  • Cover your aquarium: Having a lid on your aquarium, even just a sheet of glass, will reduce heat loss, which in turn reduces the amount of power an aquarium heater uses.

What Other Equipment Uses Power In Our Aquariums?

Surface Skimmers

Surface skimmers (not to be confused with protein skimmers in marine aquariums) consume very little power. Their sole job is to skim off protein films that build up on the surface of our aquariums. Surface skimmers are not used very often in freshwater aquariums these days.

A surface skimmer will run at around 5w so on average will cost less than 50c a month to run.

Powerheads/Circulation pumps

Aquarium powerheads and circulation pumps are very popular in larger aquariums. If you are running a 155 US Gal tank or larger, keeping the water moving around equally can be tricky. A circulation pump helps solve the problem by moving the water around.

Circulation pumps use very little power. They are essentially just an impeller spinning a fan. I use a pump that is designed for an aquarium up to 40 gallons and it only consumes 3.5w, which costs me around $0.30 a month. I also have one for aquariums up to 200 gallons and that only uses around 8w per hour, setting me back around $0.75 per month.

UV Sterilizers

UV sterilizers (sometimes referred to as UV clarifiers) are used to kill bacteria in the aquarium water and also as an aid to clearing up green water.

UV sterilizers work by passing the aquarium water over or around a submerged UV bulb. The UV light kills the bacteria as the UV light passes through it. There are two main types of UV sterilizer on the market today.

There is the passive sterilizer which fits somewhere between your aquarium and your canister filter, normally on the return pipe, and there is the active sterilizer that goes into the aquarium and has a built-in pump to move the water, much like an internal power filter.

Passive sterilizers have no moving parts. As such, their only power consumption is the UV bulb itself. UV bulbs are around 5w and so don’t cost very much to run. A 5w UV bulb will only cost about $0.47 per month.

Active UV sterilizers have an impeller running as well as a UV bulb. Luckily the total consumption will probably remain below 10w all in and so will cost less than $1 a month to run.

Aquarium Chillers

Aquarium chillers are essential when keeping fish in warmer parts of the world. Aquarium chillers work much like an air conditioning unit. Water is pumped through the chiller, coming out cooler than it went in.

Aquarium chillers are used much more frequently in marine reef tanks than they are in freshwater aquariums. If you do need to run one, you should expect the unit to consume anywhere between 300w and 2000w, costing you in the region of $30 to $150 per month!

All-in-one Aquariums

In recent years we have seen a rise in the popularity of ‘all-in-one’ aquariums such as the Fluval Flex. These small aquariums offer us the convenience of everything we need coming in one box.

Aquarium kits are good for those who are just getting into the hobby, or where a small tank is required, like on an office desk. They do have their drawbacks, however. One major drawback is that kit aquariums are often designed so you have to replace the filter media with the manufacturer’s own cartridges. Whilst we are not looking at those costs today, they should be factored in when considering the overall cost of running an aquarium.



My Final Thoughts

As you can see from the data above, there are so many variables when it comes to calculating the costs of running an aquarium. A 30-gallon unheated aquarium running a sponge filter with a basic LED light fitting can cost as little as $0.50 a month to run, whereas a 200-gallon tank running a large canister filter, 2 heaters and top of the range LED lighting may cost upwards of $20 a month.

In the scheme of things, running an aquarium is a fairly cheap hobby. If you compare your monthly fishkeeping outgoings to one night at the movie theatre, or a single round of golf, you will find you really don’t spend much money for the enjoyment you get back from your fish.


About the Author

I’ve been keeping, breeding, and showing tropical fish for nearly 30 years. Over that time I’ve done it all! I’ve had great success and I’ve made some really foolish mistakes (like the time I bought an Asain Walking Catfish). Read more…
Richard James
Editor


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