Aquarium electricity cost calculator
What does a tank actually cost to run? Enter the wattage, hours a day and your electricity rate for the monthly and yearly cost of a heater, filter or light.
The US average rate is about $0.16 per kWh; check your own bill for the real figure. A heater only draws power while cycling on, often 30 to 50% of the time, so real cost is well below this figure.
The formula
Running cost is just power times time times price: watts × hours ÷ 1000 = kWh per day, and kWh × your rate is the cost. The US average is around $0.16 per kWh, but your bill is the number that matters, so use that.
The heater is the one that cycles
A filter and light draw their rated wattage whenever they are on, so their cost is straightforward. A heater is different: its thermostat switches it on and off, so over a day it only draws power maybe 30 to 50% of the time. Treat the "heater on 24 hours" figure as a worst case; the real cost is usually well under half of it, and depends heavily on how cold your room gets.
How to spend less
The biggest lever is not the gear, it is the room: a tank in a warm room barely runs its heater. Beyond that, size the heater correctly (an oversized one is not more expensive to run, but a poorly insulated room is), and put the light on a timer. Size it right with the heater wattage calculator, and see the heater rankings for accurate, reliable thermostats.
Source
- Energy = power × time (kWh = W × h ÷ 1000); cost = kWh × rate. Heater duty-cycle range is a general approximation and varies with room temperature and tank size.
Common questions
How much does an aquarium cost to run per month?
Mostly the heater. A 100-watt heater in a normal room adds only a few dollars a month once you account for it cycling on part of the time, while filters and LED lights cost cents. Enter your wattage, hours and rate for your own figure.
How much electricity does an aquarium heater use?
A heater only draws power while its thermostat is on, often 30 to 50% of the day, so real usage is well below its rated wattage, and a warmer room cuts it further. The calculator gives the worst case to scale down from.
Do aquarium filters use a lot of electricity?
No. Most filters draw only a few watts and cost very little to run continuously; they are among the cheapest things in the tank. The heater is where the running cost lives.
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