When the Lights Go Out!

What to do in a power failure

What do rain, snow, heat, bureaucratic incompetence and Y2K all have in common? They can all cause – or at least be blamed for – a power outage.

Having the power go out for a few hours is a nuisance for all of us, but for an aquarium full of fish, it can be a life threatening experience. Here are a few tips to help keep things under control.

First of all, don’t panic. An aquarium that is not overcrowded or overfed can usually go several hours without the “life support” systems operating. You are more likely to make things worse by a drastic change, so be vigilant, but not obsessive.

Speaking of feeding – don’t! The most immediate concern during a power outage is lack of oxygen, and feeding increases fish activity and adds pollutants, both of which use oxygen. In addition, the fish may not eat well, causing even more pollution.

Leave them alone. To further conserve oxygen, leave the fish as quiet and rested as possible. Darkness is your friend. If the room is lit well enough for the fish to see you scurrying about, they may well become more active and even panic. Cover the tank with a towel or blanket if necessary.

If you were smart… you’d probably have a cheap battery-operated air pump for each aquarium in the house. They are available from better aquarium stores (order one online right now!) or sometimes at bait shops, but they’re usually sold out within a few hours of a major storm. It wouldn’t hurt to have a few extra batteries on hand as well.

A high-tech approach… would be to have a portable generator on hand, or one of those almost affordable battery backups that are available for computers.

In a pinch… some hobbyists have had success using 3% Hydrogen Peroxide (from the drugstore) to instantly increase dissolved oxygen. The dose is about one ounce per 25 gallons, more or less, so to speak. It should be added near the bottom of the aquarium (a sprayer bottle would be ideal) and distributed quickly around the tank so fish do not come into contact with the concentrated form. This is a risky treatment that should only be attempted if it is obvious that fish will begin dying soon from lack of oxygen.

Think insulation. Once you’ve covered the aeration crisis, the next concern is keeping the temperature from skyrocketing or plummeting to dangerous extremes. Even a few degrees change may bring on a future infection such as “ich”, but that can be dealt with later. If the power is expected to be out for an extended period, it’s possible that the aquarium will get so warm or cold as to kill fish outright. Covering the tank with many layers of blankets or towels will help keep it from gaining or losing temperature rapidly, and just might buy enough time for electrical service to resume.

Clean the filters. No, this isn’t just therapy to give you something to do while you wait. When the water stops flowing through a filter, the waste that has been collected begins to break down anaerobically, creating a lot of foul, dangerous by-products. When the power comes back on, these toxic compounds are pumped back into the tank.

When it’s all over… keep a close watch for the next week or so. The fish have gone through a great deal of stress and are more prone to infection. It’s also possible that some beneficial bacteriasome beneficial bacteria were lost, so have ammonia and nitrites check as well.