fish in a dark tank - what to do when the power goes out

What To Do With Your Fish Tank If The Power Goes Out

Last night I experienced one of the most devastating events for my aquarium – a power outage. It really worried me because almost the entire towns electricity cut off around 8:00 PM and nobody had a clue when it was going to come back on. As it turns out, the power outage was caused by a man crashing into an electrical pole on the highway in his pickup truck. The power was completely out until 1:30 AM or so and in the meantime I had to figure out what to do with my three fish tanks… I asked a question a forum and here’s what I learned.

Keep The Filter Media Wet

If your tank is well established (at least 2-3 months old), then you should be very concerned about keeping your filter media wet at all times. The filter media consists of the carbon, foam, bio balls, or whatever materials are inside your filter. These materials collect and grow beneficial bacteria over time that assist in killing bad bacteria and keeping nitrates, ammonia, and other bad elements low. If the media dries out, you could potentially lose all of the bad bacteria and essentially start over in the cycling process. Make sure you are keeping the filter media wet using the water from your aquarium.

Do a Water Change If Necessary

Depending on how long your electricity is out, you may need to do a water change in the pitch black. Using flashlights or candles, change the water in your tank the same way you would on your routine water changes. Even though your electricity is out, the water in your bathtub, hose, or sink should still be working. I would suggest doing a water change if the electricity is out for more than 12 hours.

Purchase a Generator

If your power is going to be out for multiple days (like when Hurricane Sandy hit the U.S. East Coast), I would suggest getting a gas generator if you value your aquarium. No filtration or light for multiple days will cause terrible bacteria growth, ammonia buildup, and stressed fish – ultimately ending in death. There are many people in the Northeast United States who lost their entire stock because of Hurricane Sandy.

Keep the Water Moving

One vital tool that shuts off without electricity is your aerator. These aerators help keep oxygen in the water, but without them, oxygen levels can get extremely low after a couple of hours. In a case like this, scoop some water out of your tank with a plastic cup and dump it back in holding the cup about 6 inches over the water. This will create some surface tension to allow for oxygen and carbon dioxide to enter/exit the water.

Reset Your Timers

When the electricity does finally come back on, make sure you reset your timers for the correct time. If the electric was out for five hours, then your lights or whatever else you have running on a timer will be five hours off schedule. Forgetting to change these back to normal could result in your light running at night which will end up causing algae blooms and stressed fish.

Wish For the Best

When it all comes down to it, there’s not much we can do about city-wide power outages. You just have to hope for the best and wait for the electricity to come back on. If you have ever experienced a power outage with your fish, please share your experiences in the comments below.

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