Update Your Site & Language

Type of Retailer

  • Premium Dealer Premium Dealer

    An officially recognized retailer offering a wide array of Fluval products and expertise.

  • Authorized Retailer Authorized Retailer

    An officially recognized retailer offering a selection of Fluval products.

  • International Distributor International Distributor

    The authorized distributor of Fluval products within a specified country or geographic region.

Items Added to Your Cart

0 Item in Cart

Shipping & Taxes calculated at checkout

View cartCheckout

Aquariums & Furniture


December 13, 2018 | By Tom Sarac

by Tom Sarac

Your aquarium’s environment is directly dependant on both you and the power source that allows key hardware to function, such as your lights, heaters, filters, circulation pumps, air pumps and skimmers. So, what happens when all of it is non-functional? What do you do in the case of a power outage?


The moment a power outage occurs, you must let common sense prevail and quickly enter prevention mode. What you can help control, you should act on –  the water temperature is one such parameter. If it’s hot outside, make sure to close the blinds to reduce the effects of the sun. If it’s cold outside, windows should be shut. If you live in an area where longer power failures are more frequent, consider purchasing a thick plastic drop sheet to place over your aquarium during power outages, as plastic is a good insulator. A battery-powered aerator is another must-have: be sure to get it set up and running before covering your aquarium.


Short-term power outages are usually of no major concern.

Those who keep marine aquariums with a sump should be wary of the right operational level. Be sure the water level increase within is contained when it is non-operational. A clearly-marked operational water line is always a good idea for any sump.

A backup battery-driven air pump is also a good idea, especially for heavily-stocked aquariums. If you don’t have one or have to take emergency measures because your fish appear to be gasping for air, rapid stirring the water surface will help oxygenate the water.


By the time you have surpassed 6 hours, you can consider the power outage to be long-term.

At this point, you may consider doing some partial water changes with warmer water if the temperature has dropped more than 5-6°F / 2.5-3°C. Your backup battery-powered aerators should be running. Do not feed your fish during a power outage!

Filters should be removed and cleaned. Give the media a light rinse and remove the bulk of any trapped debris: this will prevent any decomposition issues and formation of potentially harmful gases within the filter. Once clean, re-install the filters, but wait until the power is restored to prime them and start them up.

If the aquarium is very heavily planted and well-stocked, you may want to remove a percentage of the fastest growing types of plants and place them in a bucket of water until the power returns, as plants do consume some oxygen during darkness. Note that this is usually only necessary in the most heavily planted of aquariums.

Ultimately, the only real and complete solution is to have a generator to provide power, at least to power filters and heaters. Lighting is far less important and can remain off until regular power is restored.

Once the power is back, if the aquarium is heavily stocked, it is recommended to take an ammonia and nitrite test to ensure all is well. A partial water change at this time is also recommended.


Based on your browser settings, we've redirected you to the United States English Fluval website.

Update Your Site & Language