Preparing Your Pond for Winter 3
October is time to get your pond ready for winter. You can start by trimming back your plants. The tropical ones should either be discarded or brought into the house. Water Lilies and the more tender hardy plants, such as Arrowheads, Pickerel and Parrot’s Feather, should be placed near the bottom of the pond. The other plants can be left right where they are. It’s also important to limit the amount of leaves that get into your pond. Do this by either by placing a protective net over it, or judicious daily skimming. If you have fish, the rest of this article is for you.
As the water cools, the fish‘s metabolism slows down, they stop eating and slowly go into hibernation. They will rest on the bottom of the pond, where the water is warmest. The fish will require very little care over the next few months, but you need to ensure that no deadly methane gas builds up in the pond.
Methane is the product of decaying organic matter (dead plants, bugs and fish wastes) and it is often difficult to stop all those leaves that are blowing around from ending up on the bottom of your pond. Methane escapes at the water’s surface, but when the pond is covered in ice, the methane is trapped and the levels build up to the point where it will poison all of your fish.
The solution is to keep a hole open in the ice, but please, don’t go chopping the ice with an axe. Fish are sensitive to minute pressure changes, as each strike would feel like a bomb blast. A better way is with a floating heater, like the ones used for stock tanks. They will keep a hole open, but most of them consume a huge amount of power.
A more efficient solution is to use an air pump, which pumps air bubbles into your pond. As the air rises back towards the surface, it will carry with it some of the warmer water and this keeps a hole open. Make sure the end of the air tube is 6 to 12 inches above the bottom of the pond, so that the warmest water at the very bottom where the fish hang out is not disturbed. I like this method because it also increases oxygen levels, and even if the hole closes over for a few days during extreme cold, the air (with the methane) will find a way out of the pond. I have been doing this for many years and it has never failed me. The only thing to watch for is if you have a power failure, as the water can sometimes back up the tube and freeze at the surface, thus blocking the vital flow of air. If that happens, you can thaw it out with hot water, or drill a small hole in the ice near the blocked tubing and put in a new tube.
So other than checking the methane hole once in a while, you can enjoy your winter activities and be assured that all will be well when your pond life wakes up in the spring.