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Will your electricy bill go up when you have a fish tank?

Will having an aquarium make your electricity go up a lot?

Well, let’s run the numbers and find out!

First, we must figure out how many watts each item uses that we’ll need for an aquarium. You can find how much your equipment uses by looking at the back of the box or the tag that is on the cord of your item.

Here’s what I use in my aquariums for a 20 gallon fish tank:

Heater: 100 watts

Light; 40 watts

Filter: 10 watts

Total = 150 watts

That’s all I keep in mine and it’s probably the same for most folks but if you have an UV sterilizer, co2 system, extra heaters, wave makers, etc - you’d want to add those into this calculation.

Now for the fun part, math!

Once you know how many watts each item uses, you’ll need to figure out how many kilowatts per hour it uses.

If this aquarium uses 150 watts 24/7 for the entire year we would have used 1,310,400 watts (150 watts 24 hours 7 days a week * 52 weeks = 1,310,400) or 1,310.40 killowatts. Just divide your watts by 1,000 to get the kilowatts.

Now that we have how many kilowatts we use per hour per year, we need to find out how much your area charges per kilowatt hour.

In my area, they charge about .15 cents per kilowatt hour. To find yours, you can open your energy bill and take the bill amount and divide by the kWh that you used that month (your bill will show your usage in kWh on your statement) and the number you end up with is approximately how much your area charges per kWh.

So, if we multiply 1,310.40 kWh * .15 cents we get $196.56. That means for an entire year if the light, filter, and heater are on 24/7 we would be charged $196.56. On a monthly basis this would calculate to be an extra $16.38 on our electricity bill.

Was this more or less than you expected?

Now, the real cost is actually lower since the heater and light will not run 24/7. So, if we want to figure out a more accurate cost we would have to make some assumptions.

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Let’s say that each item runs for 8 hours, with the exception of the filter which will run 24/7. The kilowatts per hour would then be:

Filter: 10 watts 24 hours 7 days * 52 weeks = 87,360watts/hour = 87.36 kWh

Light: 40 watts 8 hours 7 days * 52 weeks = 116,480 watts/hours = 116.48 kWh

Heater 100 watts 8 hours 7 days * 52 weeks = 291,200 watts/hour = 291.20 kWh

Total = 495.04 kWh/year or 41.25 kWh/month

So, on a yearly basis this aquarium would cost us:

495.04 kWh * .15 cents = $74.26

And on a monthly basis it would be:

495.04 kWh * .15 = $6.19

If we look at the numbers, we see that the heater uses the most energy! So, if you are looking to cut electricity cost - having an aquarium without a heater will help a lot! But obviously this is not possible for everyone.

What are some ways you lower your enery cost when it comes to aquariums?

In our next newsletter, I’ll show you how to save on energy cost if you have a lot of aquariums like I do! (I have 30 aquariums currently)

Until next time!

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