Pond heaters are now commonly put into use as winter weather arrives in many parts of the country. And although it’s a simple and affordable device it can pay off handsomely when it’s installed in a small koi or fish pond.
For many people, wintertime means their ponds will be shut down, covered over, drained, and put to bed for a few months. If one has fish, they are often moved indoors and held in temporary tanks.
Others however are finding enjoyment in their water gardens throughout the seasons including the frosty days from November through Febuary. If your pond is set up right for it, wintering fish outside isn’t much of a problem and in some settings a pond heater will be an important tool to use.
In climates where you know you’ll get below freezing for weeks at a time, it’s best to have a pond that’s over 24 inches or greater. The deeper the better is the general rule. Fish tend to go lower in a pond since it’s a bit warmer there than towards the surface. Even if a pond were to freeze over completely for a bit, in many cases the fish will fair alright.
So where does a pond heater come in handy?
First, they’re very effective at keeping a portion of the surface free from ice. This opening doesn’t have to be very large, but as long as it’s present, there can be an ongoing exchange of gases (some of which can be toxic to fish) that can exit the pond and fresh oxygen can get in.
In fairly deep ponds or those of four feet or more, it’s useful to suspend the pond heater or in some cases you’d hear them called de-icers, at or near the surface of the pond. Some of these come with floats which make this easy.
In shallower ponds the floats can be removed and the heaters can be placed at the bottom which helps to avoid any complete freeze ups, which is something it’s best to avoid.
When choosing a fish pond heater, look for one that’s rated for your particular climate zone. In moderate or mild climates a very low watt device (250 watts) will be ideal. As the temperatures drop more, you’ll want to increase the wattage capability of the unit.
In addition, larger pond will require a higher wattage heater in order to help keep it open from ice build up.
For the most part, the heating devices are very simple to use. Just place them in the pond and plug them in. They will usually work well all season long. However it’s advisable to keep an eye on things and make sure a part of the pond’s surface is staying open. Heating elements can burn out and power outages can occur so it’s good to monitor this situation.
We get asked alot about aerators for winter use and while we like them, we normally won’t suggest their use in very brutal winter conditions where they may not be able to keep the ice open. Even streams can freeze up when it’s cold enough so for most northern locations in the U.S. and Canada, a pond heater will be your best bet at protecting your pond and it’s inhabitants from the coldest conditions.