Dealing With a Power Outage: Aquariums and Ponds
Millions of residents in numerous states are without power following the destructive force of Superstorm Sandy. Many of these individuals undoubtedly own aquariums filled with valuable fresh or salt water fish. With restoration of power perhaps several several days away in some hard hit areas, what should an aquarium owner do? Dr. Greg Lewbart, professor of aquatic, wildlife, and zoologic Medicine at NC State College of Veterinary Medicine, offers some advice.
By Dr. Greg Lewbart MS, VMD, Dipl. ACZM
In the In December 2002 the numerous cracking boughs and fiery transformers awakened me to the importance of a contingency plan for pet fish when electricity stops. Much of this information applies to power outages regardless of the cause. Please feel free to pass this document along to anyone that may benefit.
Food: Do not feed your fish during a power outage. In warmer months the act of eating and digesting will use valuable oxygen. In winter your fish will likely have plenty of oxygen but will probably be uninterested in food with a slowed metabolism. Furthermore, uneaten food will only pollute the aquarium or pond with unnecessary nitrogen.
Temperature: In winter, try and insulate your aquarium with a blanket, sleeping bag, or newspapers. In summer, remove anything from the surface of the water in an effort to increase the surface area and hence gas exchange efficiency. Obtain an aquarium thermometer and have it handy to monitor the water temperature. Most tropical fish can tolerate temperatures in the low 60’s(F) or even high 50’s for several hours. Once temperatures dip to the mid-50’s action should be taken to elevate the temperature. Here are some options:
- Obtain an alternate power supply to run the heater and pump/filter. This could be a generator or creatively used extension cord to a location with power.
- Obtain an alternate and safe external heat source such as a propane or kerosene heater.
- Physically transport the fish to a warmer location. Heavy-duty zip-lock bags work well for this purpose. Fill the bag with one third water and two-thirds air. Pure oxygen is even better than air. As long as the external temperature is adequate, sparsely packed fish (five inches of fish per gallon) should survive for at least 36 hours packed in this manner. Alternatively, any secure vessel such as a bucket, tub, or large jar can be used to move fish to a safe location. While moving the entire aquarium is an option, it will usually present some logistical challenges. If one decides to move the aquarium, then up to 70% of the water may be discarded before the move to make transport easier (remember, a gallon of water weighs eight pounds). If the problem is water that becomes too warm, make sure that exposure to direct sunlight is minimized or eliminated. In most situations tropical and even temperate fishes, like goldfish and koi, should be able to tolerate water temperatures in the high 80s or even low 90s for a day or more. One risk of prolonged exposure to these high temperatures is low dissolved oxygen. Manually stirring the water with a whisk or similar implement can help elevate oxygen levels until power returns.
- In the case that the fish cannot be moved, and the water temperature reaches a critically low level, warm dechlorinated water can be added to the aquarium. A thermometer should be used to be certain that acute changes to do not exceed five degrees. Generally, a 10% water change with warm water every hour or two should safely increase an aquarium’s temperature without endangering the fishes.
Temperate species such as goldfish, koi, and North Carolina native fishes should be fine without changing anything in the environment. If the power outage persists and the surface of a pond freezes over, the ice can be mechanically broken to form an “air hole.”
Only as an absolute last resort should fish from one aquarium or pond be mixed with fish from another aquatic system. This practice greatly increases the risk of spreading infectious viral, bacterial, fungal, and parasitic diseases. It may also lead to inter or intraspecific aggression.
Water Quality: The longer fish remain in unfiltered water the worse water quality parameters will become. Again, do not feed fish while there is no power and try and test the water for elevated ammonia levels. Most fish can survive days or even weeks without food. If ammonia levels increase above one (1.0) ppm then water changes (10-30%) are recommended.
Lighting: The least of your worries. Ornamental fish will survive indefinitely without fluorescent/ supplemental lighting. This is of more concern with tropical reef aquaria where live sponges and coral are maintained. Many of these invertebrate species rely on bright light and the symbiotic organisms the light supports.
Supplies to have available:
Zip-lock bags (various sizes)
A net (note: herding fish into a plastic bag using a net is a much safer way to capture fish than using a net on its own. Nets can damage the protective mucus layer and sensitive epidermis.)
Propane or kerosene heater
Oct. 30, 2012