Emergency Maintenance
If you stay with the hobby long enough, you will likely be faced with emergencies of one type or another, no matter how carefully you plan. Being prepared ahead of time can make the difference between an inconvenient situation and the loss of your entire collection.
One of the most useful pieces of emergency equipment available to the aquarist is the battery operated aerator. Originally sold to keep baitfish alive on fishing trips, units of all sizes are now available in pet stores as well as in bait shops. Be sure to purchase enough units to supply oxygen to all of your tanks in the event of a power failure (because when filters shut down due to an electrical failure your pets will be denied the oxygenating effects of water movement). Pet stores also sell tablets that dissolve in water and release tiny bubbles in the process, but these seem not nearly as effective as battery operated aerators. Aquariums may also be manually aerated by scooping out water and pouring it back into the tank from above the water's surface.
In the event of a thermostat malfunction that overheats your water, a partial water change with water of a cooler temperature may be necessary. Be sure that the water you add is not so cold as to cause an extremely rapid change in temperature. A gradual temperature change, even if it takes a longer time to reach the ideal temperature level, is preferable to a drastic drop in temperature. Aquarium water may also be cooled by floating hot water bottles filled with ice or cold water in the tank. In all cases, be sure to carefully monitor the temperature with an accurate aquarium thermometer.
If your pets have survived a temperature emergency and are living in water that is too hot or too cold, be sure to readjust the water's temperature gradually. A sudden change will stress most aquatic animals and may kill them outright or leave them open to disease and parasitic infection in the near future.
If a power failure during cold weather renders your aquarium temperatures too low, the water should be gradually reheated through the addition of warmer water or by floating hot water bottles in the tank. Water loses heat fairly slowly, so you may be able to offset a short term power loss easily in this matter. In the event of a longer emergency, keep on hand enough insulating material to wrap completely around all of your aquariums. By doing this you will greatly reduce the rate of heat loss from the water.
