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Surviving Power Outages

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No matter what time of the year it is, or what reason the power goes out, we should all be prepared to handle this situation at any given time! An aquarium can survive for a little while without filtration, but not for very long without heat and oxygen. Things can quickly get out of hand and turn into a disaster if these two life giving factors are not taken care of right away, especially if cold outside weather is contributing to a continuous drop in the room temperature where an aquarium is kept. A portable generator is the best solution to a long-term outage but if you can't afford $500+ for one here are some tips to help you be ready the next time the lights go out.

First things first.

The first thing to do in an outage is to unplug your filters. If the power is off for long a long time, toxins such as hydrogen sulphide and ammonia build up in the filter. When the power comes back on, the filter will spew this toxic cocktail back into your tank, perhaps killing the fish. Once power is restored, clean out all filters before using them.

Preserving biological filtration is another matter. If you use rotating biowheels, remove them from the unit and submerge them in the tank proper. For fluidized bed filters, remove as much water as possible from the unit, leaving the sand covered by only 1/4" to 1/2". For trickle filters, you can pour water through them once an hour or so or wrap them in plastic film in order to maintain humidity.


Unless you know the power will be off for a long time, do not feed the fish. Most fish can survive 3-5 days without feeding. If you must feed (for the health of the animal or your own piece of mind), feed sparingly. Remember, your tank's life support system has been compromised, and adding more organics will hasten water degradation.

Penn Plax Pump

This battery powered air pump is an automatic back-up system that keeps your fish alive in the event of a power outage. Comes with 20" of airline tubing and an airstone. Operates on two "D" cell batteries (not included). The pump will activate automatically upon detecting a power outage (you must plug it into an electric unit). Can also be used as a portable pump.

Oxygenation Methods

The best way is to purchase a battery operated pump like the one above.

You can use the manual method: Scoop tank water into a clean, sterile cup, pitcher or container of some kind and lift it above the water. Pour that water back into the tank from a distance above. The higher you pour the water from above the tank, the better oxygenation you get, and it helps to keep some water movement going. To avoid messing up your substrate and stirring up a bunch of crud off the bottom, put a dinner plate on the bottom of the tank or sit it gently on top of some rocks or coral near the top of the tank and pour the water onto the plate area. If you are doing this using the floating hot water container method above for generating heat, slowly pour the water over the top of the floating containers. Remember again, heat rises. Any generated heat from the floating containers will stay near the top of the tank where the containers are. You need to get some of this warmth to the bottom of the tank, and this is a good way to do it.

How To Generate Heat in an Aquarium

Heat rises! Covering the top of your tank, particularly in the winter time is very important. Block off any hood vents that might allow heat to rise and escape. LEAVE VENT HOLES! Newspaper has amazing insulation factors. Wrap the outside of your tank with a thick layer of newspaper to help retain some of the heat.

You can generate some heat in your aquarium by using hot water. Purchase a propane camp stove, portable stove (like the ones hikers and campers use), BBQ, or any similar piece of equipment to heat water with that does not require electricity to run. Besides, you can eat some hot meals this way too!

NEVER POUR HOT WATER DIRECTLY INTO AN AQUARIUM!!! Take a sturdy plastic container and put hot boiling water into it and cap it tightly (we tested this method using a thoroughly cleaned 1 gallon Clorox jug), then float the sealed hot water jug in your tank. You can fill the container with whatever type of heated water you want, but removed aquarium water works well. Keep in mind that when you a place container(s) into your tank water, the water level will rise, so you may have to remove some tank water anyway. Use common sense on this one. Use water that is safe to put in your tank, in case some of the water leaks out of the container. Once the hot water has started cooling off in the container, just replace it with more hot water. We tested this out on one of our tanks that was at about 78 degrees and it took 45 minutes for the water to be completely cooled off in the jug. You can float multiple containers at the same time. You can decide for yourself how many depending on the size of your aquarium and how cold the tank water is getting. This method will not maintain high temperatures in your tank, but it will help to generate some heat back into the tank so it doesn't keep getting colder.

Back Up Ammonia Buffer

If your system ends up being shut off for a period of time, test the aquarium water periodically to be sure ammonia is not starting to accumulate. Keep a supply of AmQuel or other type of ammonia destroyer at hand. If you start seeing a rise in ammonia due to the lack of filtration, you'll be ready.

If you follow our advice, your aquatic charges should make it through the power outage with little or no problems. Once the outage is over, do a 25% water change and replace the carbon or whatever chemical filtrants you are using. Also watch for signs of disease (mostly Ich, which looks like white spots) and treat as necessary.

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