It is only natural to put fish in your pond for the enjoyment of watching them but the way we feed them depends on the weather. During the cold winter months fish live off their stored body fat and will go into a rest period. What you feed your fish is dependent on your water temperatures. Give them high protein food during the warm months and high carbohydrate foods during the early spring and autumn. You may want to purchase a pond thermometer to monitor the temperature and place it 10-12 inches below the surface of your water.
As winter passes and spring arrives with water temperatures being below the 50s, the fish have been experiencing a form of hibernation. Their metabolisms are too slow during the cold period to be able to digest food so you don't want to feed them. Their activity is minimal as they survive the winter months by burning the stored body fat they accumulated prior to winter.
On the few warmer days of spring they will come to the surface acting as though they want fed. The water should be stabilized around 50 degrees before you resume feeding your finned pets. You will want to feed them easily digestible food, such as a wheat-germ-based floating pellet to start with since their digestive systems are still slow. Microbe-Lift makes a Fall/Spring Fish food that is wheat germ and easily digested. Feed the fish in the morning, feeding them lightly at first so that they will digest their food before the temperature lowers at night for a couple weeks. Once the water temperatures rise above 55 degrees resume feeding them their normal high-protein food.
Once autumn starts approaching and the water temperatures begin to cool, switch back to the wheat-germ-based food. Begin to taper off the amount of food as the appetite of your fish starts to decrease.
A good rule of thumb is to only feed your fish what they can consume in a 5 to 10 minute period. You can then net out any left over food so that is doesn't sink and rot in your pond causing more sludge. When your water temperature falls to below 50 degrees you want to stop feeding them completely.
You may want to add some flake food or balls of cooked oatmeal to your feeding regiment for the baby fish once they start to appear in early spring.
Adding fish to your pond can be a rewarding experience and you'll have yet another thing to enjoy while relaxing by your pond.
Buy pond thermometer and pond fish here.