As the temperatures continue to drop outside, the heaters in our aquariums turn on more frequently. This, by itself, is not an issue. However, if the water level in your sump or aquarium drops below the heater, you can run into some serious issues. When the water level drops, the heater is exposed to cooler air and will want to try to heat it. This obviously cannot be accomplished, so the heater remains on. As the heater’s temperature climbs, whatever it is touching is in serious risk of being burned. This can include plastic components, such as an acrylic sump. The glass of your tank can even break if it gets too hot. If you find your heater exposed, do not put it into the water because it will crack instantly and get glass in your tank. Instead, unplug the heater and let it cool off on its own.