For a small pond, ice-skating is not a very good option. The ice may get thick enough to do that, but most people's concern is for their fish. Are they all right down there? Do they need to eat? Where are my frogs?
Winter brings about a completely different appearance for the water garden, one that is very interesting yet a bit stark. The very nature of the changing of the seasons is what makes a water garden so exciting. You get a different seasonal look with one garden!
Once you reach the stage of a frozen pond, you should have no plants showing except those that you allowed the foliage to dry for winter appearance. The dried stems and foliage protrudes through the ice, giving texture and visual depth to the garden. All of the water lilies will be more or less empty pots of soil with no leaves showing other than those at the soil surface.
If you have located a water garden properly in your landscape, it is situated where you see it daily, near a window, patio or some high traffic area. For this reason, you want the pond to look good year round. If you have a waterfall you will want to keep the water flowing so you can enjoy the ice formations and trickling sounds. As long as the water is moving, it will not freeze in the pipes. The best ice formations occur when the temperatures have been below freezing for a while. The ice builds up along the edges of the water flow, making a gnarled mass of ice that grows with the splashing of the water. Watch out that the ice does not form a dam across the spillway, this could divert the water out of the falls. This is not likely since the moving water keeps a channel open for the water to flow through. It is a good idea to look out for this problem, because it can happen, though rarely. As the ice enlarges, it will become thicker and may eventually grow over the spillways entirely. The water will continue to move under the ice and its movement is apparent by its sound and even by the undulating water below the clear ice.
Low voltage landscape lighting further enhances the frozen pond and waterfall. The light reflects magnificently across snow and ice, creating a winter wonderland that is a real treat when viewed from inside a cozy living room. A small five watt light goes a long way when it's light is refracted into a multitude of colors beneath the contorted ice. Higher wattage lights create some heat; enough to keep some ice from forming in a waterfall. The typical submerged light is a twenty-watt spotlight that may be deep under the water or hidden in a pocket of water in a cascade. This type of fixture is often tucked into the side of a pond in the stone work above or below the water. Above the water this light grazes the surface, highlighting a feature such as a statue or an interesting rock. Exercise care not to overdo light in and around a pond. Too much light destroys the effect of individual fixtures. Pick two or three items to feature and add the mystery of darkness, too.
A pond without a waterfall can still have an alluring appeal. With the water pressure from the pump directed toward the surface of the pond, the undulating motion of the water keeps the surface ice-free. The bubbling action can be very slight if the water is discharged from deep in the water. A pump sitting near the bottom and pushing water upwards will cause a gentle movement with a very light sound. Put a tube on the outlet of the pump and bring the pressure closer to the surface, and the movement of the surface becomes more pronounced. Discharging water immediately below the surface will create a small geyser that produces a significant sound, audible from many feet away. As the season gets progressively colder and ice begins to build around the perimeter of the pond, the moving water will not freeze. This will make a circle of water surrounded by thickening ice. This hole in the ice will allow free movement of gasses in and out of the water while entertaining you with constant surface movement. Add to this a low voltage light that is attached directly to the outlet of the pump and the night will be illuminated with a dancing light show that is brightly visible from a great distance. As the ice forms closer to the gurgling motion, the light becomes diffused and the whole pond surface begins to glow.
In times of short-term freezes or in milder climates where freezing is not very deep, statuary can be left operating. Ice tubes will form from the outlet of the statue to the pond surface. The larger the outlet of the fountain ornament, the less likely it is to freeze. Be careful not to allow long-term freezing to damage the ornament. Instead it is advisable to disconnect the statue from the pump and let the water discharge towards the surface for the geyser affect.
One popular method of keeping the pond from freezing entirely is to employ the use of a floating electrical deicer. These units are used around the farm to keep water thawed for livestock in the water troughs. This system is especially popular with bird watchers since it provides a continual supply of drinking water for their feathered friends. Birds will come to the edge of the hole in the ice to drink and even bathe. This is an expensive method of de-icing a pond since power use is considerable with most units. If the birds are the main reason to keep a hole in the ice, this is by far the best way to do it. Birds will not be able to get as close to the gurgling movement as they can a patch open water that a deicer makes. Low wattage deicers are made for patio ponds that can be used to make a small hole in the ice. These 250 or 500-watt systems will keep a hole in the ice a few inches wide. More powerful units are needed in colder climates or where winters are severe.
We can take a cue from Mother Nature; let the pond freeze and don't worry. This is fine as long as the water garden is relatively clean. An inch of leaf debris is not enough to cause a problem, but much more than that can create an oxygen depletion that is fatal to fish. As the leaves decompose, oxygen is used in the process of decomposition. If the pond is frozen over, fresh oxygen can not be replenished. Never, under any circumstance, should the ice be broken by striking the surface of the pond. The percussion caused by hitting the ice will break or damage the air bladders of the fish, resulting in their death.
Oh yes, your frogs will be fine. Nature has a way of taking care of her own. They burrow into the mud of the plants and wait out the cold weather. The fish will hide in the shadows for the winter, coming out to eat only when the water warms up into the fifties.
Enjoy the winter water garden, you will find it a fascinating time of year when more goes on than you realize. You can make it even better by running the waterfall or fountain, and more so by illuminating your creation.