A reef tank electricity cost calculator estimates how much it costs to run your saltwater aquarium each month and year, based on the wattage and runtime of every piece of equipment in your system. Use this aquarium wattage calculator to plan your fish tank running cost and compare reef tank power consumption across LED versus T5, AC versus DC pumps, and other gear choices.
Need full setup and ongoing budget instead? Try the Free Reef Tank Cost Calculator for equipment, livestock, supplies, and total reef budget.
Add every piece of reef tank equipment that draws power. Pick a preset for typical wattage, then adjust to match your gear and schedule.
| Equipment | Watts | Hrs/day | Qty | kWh/day | Monthly | Yearly | % of bill | |
|---|---|---|---|---|---|---|---|---|
| 1.20 | $5.84 | $70.08 | 21% | |||||
| 2.40 | $11.69 | $140 | 41% | |||||
| 1.08 | $5.26 | $63.07 | 19% | |||||
| 0.48 | $2.34 | $28.03 | 8% | |||||
| 0.36 | $1.75 | $21.02 | 6% | |||||
| 0.07 | $0.35 | $4.20 | 1% | |||||
| 0.24 | $1.17 | $14.02 | 4% | |||||
| Totals | 5.83 | $28.40 | $341 | 100% |
Quick reef tank power consumption comparisons at your current kWh rate. Use these to decide if upgrading lighting or pumps is worth it.
Estimated monthly cost for typical fixtures over a 4 ft reef.
LED saves about $13.64/mo vs halide at this rate.
Annual electricity cost at your kWh rate.
Tunable DC pumps can save more if you run them below max flow at night.
List every piece of gear that draws power: lights, heater, return pump, wavemakers, skimmer, controller, ATO, UV, reactors, and chiller. Pick a preset or enter a custom name.
Use the wattage on each device label. For heaters and chillers, use an effective duty cycle (typical reef heaters run roughly 8 to 14 hours equivalent per day).
Enter your local electricity rate per kWh. The calculator shows daily kWh, monthly cost, annual cost, and the share each item contributes to your reef tank power bill.
Most reef tanks fall into a predictable pattern of power consumption. Lighting, the heater, and (when fitted) a chiller dominate the monthly electricity bill, while small 24/7 loads like return pumps, wavemakers, and skimmers add up because they never turn off. The table below lists typical wattage for common reef gear so you can sanity-check your aquarium wattage calculator inputs above.
| Equipment | Typical wattage | Hours/day | Notes |
|---|---|---|---|
| Reef LED light | 60-250 W | 6-10 | Scales with tank length and PAR target. |
| T5 fixture | 96-432 W | 8-10 | Higher draw than LED for similar coverage. |
| Metal halide | 150-500 W | 6-8 | Highest electricity and heat output. |
| Heater | 50-500 W | 6-14 (duty cycle) | Sized to tank volume and room temp. |
| AC return pump | 30-90 W | 24 | Always on - small wattage adds up. |
| DC return pump | 15-50 W | 24 | More efficient and tunable. |
| Wavemaker / powerhead | 10-45 W each | 24 | Quantity matters - many tanks run 2 to 4. |
| Protein skimmer | 8-40 W | 24 | Needle-wheel pump runs continuously. |
| Chiller | 150-600 W | 1-6 (duty cycle) | Mostly summer; can dominate bill on hot days. |
| UV sterilizer | 9-55 W | 8-24 | Optional; many run only during outbreaks. |
| Controller / ATO / dosers | 3-15 W each | 24 | Low wattage but cumulative. |
Heaters and chillers don't run continuously. Use an effective duty cycle (often 8 to 14 hours/day for heaters in a normal room, less in summer) so the electricity total reflects real reef tank power consumption rather than nameplate watts.
Most reef tanks cost between $15 and $80 per month in electricity, with smaller nano tanks at the low end and large mixed reefs with chillers at the high end. The biggest variables are lighting wattage, heater size, whether you run a chiller, and your local kWh rate. Use this aquarium electricity cost calculator to get a number specific to your equipment.
Lighting and heaters are usually the top two power draws on a reef tank, followed by chillers if you run one. Return pumps and powerheads add up because they run 24/7, even though their wattage is lower. The percentage column in this calculator highlights which items are driving most of your bill.
Yes, LED reef lights typically use 30 to 60 percent less electricity than equivalent metal halide and meaningfully less than T5. A 150 W LED running 8 hours a day costs far less than a 250 W halide on the same schedule. Switching from halide to LED can pay back the fixture cost in a couple of years on most reef tanks.
Yes. DC return pumps typically draw 40 to 60 percent less wattage than AC pumps at similar flow rates because they use efficient brushless motors and can be tuned down. For example, a 25 W DC pump running 24/7 versus a 45 W AC pump saves roughly 175 kWh per year, which is about $28 a year at $0.16 per kWh. Use the comparison panel below to model your specific savings.
The highest-impact moves are: switch metal halide or older T5 to efficient LED, replace AC return pumps with DC pumps you can tune, insulate the room or use a smaller tank to lower heater runtime, run the chiller only when needed, and schedule lights for shorter photoperiods. Even trimming each light hour by an hour per day can save 5 to 10 percent on lighting cost.
Estimate full setup and monthly costs across equipment, livestock, supplies, and electricity.
Pick the right heater wattage for your tank size, ambient temp, and target reef temp.
Confirm true water volume so equipment sizing and cost estimates start from accurate gallons.
Match a skimmer rating to your bioload before locking in pump and skimmer wattage.