How to care for your pond in winter

Leaf Fall.
Leaves and other plant material will, if allowed to accumulate, poison a pond (particularly small ones) as toxins are released as part of the process of decay. It is essential to fit a pond net to prevent leaves from falling into the pond during the autumn months. (See – ‘Pond Maintenance’ & ‘Pond Cover Nets’ sales areas on this website.)

Pond Plants.
Marginal plants should be cut back as the foliage deteriorates and failing lily leaves should be removed. This will prevent pollution of the pond as in ''Leaf Fall'' above. Pond and bog plants sensitive to frost should be protected with straw or fleece, or removed to a frost free area such as a greenhouse to over-winter. Certain types of plants may need specific treatment (e.g. bog Cannas which should be lifted, taken to a frost free area and allowed to dry out completely until re-potting and fertilising in early spring).

Feeding Fish.
When the average water temperature reaches 55F (10C) you should stop feeding your fish with their usual food and switch to a low protein or, ideally, a vegetable based food supply. This is because it is difficult for fish to digest proteins at lower temperatures. The most commonly used winter feeds are wheatgerm based in either a stick or pellet form. Some pond foods, such as the Phoenix range, are vegetable based and can be fed the whole year round. When the temperature reaches 45F (7C) you should stop feeding your fish completely as even low temperature feeds cannot be digested at temperatures lower than this. Caution: Feeding your usual food to fish at temperatures below 55F (10C) can result in intestinal or stomach ulceration as the food sits undigested. (See – ‘Pond Winter Food’ sales area on this website.)

Fish Disease Prevention.
During the autumn and early winter months, (as temperatures drop from late September to October - UK calendar), the immune systems of pond fish become repressed as their metabolic rate slows. This leaves them susceptible to attack or damage from disease causing pathogens present in the pond. To help the fish through this period we recommend addition to the pond of a broad based chemical treatment to keep the levels of these disease-causing organisms low so protecting the fish. Apply such treatments for about four to six weeks from when the temperatures drop. (See – ‘Pond Treatments - Fish Disease’ sales area on this website.)

Filter Maintenance.
When the water temperature reaches around 50F (10C) the biological activity in a pond filter reduces considerably. This is the time to strip and clean filters and ultra violet sterilisers and disconnect them until the temperature rises in early spring. (See - 'Information Helping you to Choose a Pond Filter' and 'Information Helping you to Choose an Ultra Violet Steriliser' for more details.)

Ice On The Pond.
If the pond becomes completely covered with a layer of ice for any amount of time this can have serious consequences for the fish it contains. Gases are trapped in the water by the ice layer and oxygen is depleted and this drives the fish towards the surface as they attempt breathe. They can then become trapped in the thickening ice layer with fatal results. Fitting of a pond heater which can be considered a temporary installation for when the weather is particularly severe will keep a small area free of ice and allow the essential gaseous exchange. Pond heaters use only about as much power as a house light bulb and are fairly inexpensive. There are also available devices which do not use electricity. (See Pond Winter Anti Ice Devices sales area on this website.) Leaving a football in the water does not work and cannot be recommended. Never hit the ice to break it as this will send shock waves through the water which can kill the fish.

General Recommendations.
As a general rule it is best not to run aggressive waterfalls, fountains, etc., during the cold winter months. This is because a warm layer of water forms at the bottom of the pond generated by heat from the underlying ground. At the coldest times fish become semi torpid and sit almost motionless in this slightly warmer layer helping them to get through the worst of the winter. Aggressive circulation mixes the colder surface layers with this haven of warmth and can reduce the prospect of the fish surviving the winter.

Certain types of pond pumps if not run during the winter will require removing, stripping and greasing. Please refer to manufacturer's recommendations.