In the fall, you need to prepare your pond for winter. This does not require a lot of work, just simple maintenance jobs.
Clean any excess debris from the
bottom of the pond. Decomposing debris will create unhealthy gases that can be
harmful to your fish if trapped under the ice without any way to escape. You can buy
rather expensive “pond vacuums” that use water pressure to suck up debris
and discharge it outside of your pond through a hose. I use a dull long-handled
garden hoe to gently scoop the stuff out. Dull is the key word here. Be
extremely careful not to puncture your liner.
If you have trees nearby, you can buy netting to stretch over your pond and keep the leaves out. I did this and worked great.
If you have an external filter, remove it for the winter so water does not freeze in it. Give it a good cleaning and store it inside for the winter.
Turn off your waterfall. If the water freezes, it could topple your rocks into the pond.
You will need to keep at least a
small area of your pond unfrozen all winter to let oxygen in and gases out. The
best way to do this is keep an area of water moving. Moving water will not
freeze except under the most extreme conditions. Simply having a small fountain
running into the pond will usually do the trick.
Again, you can buy pond heaters
and floating heaters but they are expensive and expensive to operate. There are
also oxygenators, aeriators, floating water circulators, and all kinds of gizmos for sale
if you want to spend the money.
I bought a little thing for around
$60 that amounts to floating Styrofoam ball attached to small pump by a hose.
The pump is suspended just above the bottom of the pond by the floating ball.
Water is pumped up the hose and discharged just under the floating ball. The
idea is that the moving water discharged around the floating ball will provide a
small circle of water that won’t freeze. My little Styrofoam ball was solidly
encased in ice at the first freeze. It seems the pump did not provide enough
volume and it’s tiny inlet filter also quickly clogged up diminishing its
volume even more. Oh well, live and learn.
I simply left my little fountain in the middle of pond running all winter and everything was fine. Even when we had a 2-3 inch thick coating of ice over most of the pond, the area around the fountain never froze.
IMPORTANT! NEVER, EVER, pound on the ice to break it up. The shock waves in the water can stun or even kill your fish. If your pond does freeze over completely, fill a hot water bottle with hot water and lay it on the ice. It will melt through the ice and then float on the water.