Spring
As the days get longer and the temperature rises Spring is the time when the pond starts to come to life. Your fish become more active & start to look for food & the plants begin to grow again. While the water temperature is below 10ºC (50ºF) it is advisable to feed your fish an easily digestible wheatgerm food. Whilst your fish may be hungry it is important to feed them sparingly as friendly filtration bacteria that breakdown poisonous fish waste will still not be present in high numbers after the cold of winter. These numbers can be boosted by adding Interpet Bio Start or one of the other bacterial products.
Late spring is the ideal time to replant your pond. Stockists will have a good range of healthy young plants. This will give the plants the maximum time for growth before the onset of the colder months. The addition of a special pond plant fertilizer will boost this growth further.
It is particularly important to test the water for pH, ammonia, nitrite & nitrate throughout spring. The increase in the fishes metabolism, coupled with more frequent feeding, can cause water quality problems. On top of this the filter is not working at peek efficiency and there may be decomposing vegetation from plants that died over winter. If you detect a problem, stop feeding the fish and carry out a water change of no more than 25%. Remember to add a dechlorinator when using tap water. This will dilute any toxins and reduce the problem short term.
Over the winter pumps, filters & Ultraviolet clarifiers, may have been switched off or running at a reduced level. Now is the time to check these are in full working order. Clean & check your pump, not forgetting the impeller. Wash out the sponges in the filter & replace if over two years old. If your pond is fitted with a UV check it for signs of frost damage, clean the quartz sleeve & replace the UV lamp. The lamps only have an effective life of between six & twelve months. Replacing it now will prevent early algae growth caused by the longer days. If you have been using a pond heater remove this if there is no chance of a hard frost.
During the spring it is important to keep a close eye on your pond fish for disease. At this time of year the fishes immune system is at it's lowest level leaving it open to attack by disease causing organisms. It can be worthwhile adding a broad spectrum treatment in early spring that protects them until the immune system starts functioning again. Myxazin P manufactured by Waterlife research is an effective broad spectrum treatment.

Summer
With long hot days of summer the pond is buzzing with activity, plants are flowering and the fish are feeding vigorously. As the water is now much warmer you can switch from a
wheatgerm food to a staple diet. Feed your fish enough food so that it is eaten with a few minutes two or three times a day. You can give your fish a treat occasionally by feeding them live or frozen Bloodworm or Daphnia.
It is still worth testing the water to check that the filter is coping with the increased loading. If there are persistent problems it could mean your pond is overstocked or your filtration system is not powerful enough.
Filters & pumps will need frequent cleaning to ensure a constant water flow through them.
Filters and pumps should be left running twenty-four hours a day. Changing 25% of the water once a month during the summer months can reduce high levels of nitrate, one of the main causes of algae problems. As the water temperature rises the amount of dissolved oxygen available to your fish decreases. Keep a close eye on them in very hot or stormy weather, if they start to gasp at the surface this indicates a lack of oxygen. This could be caused by a problem with your water pump, although a more likely cause is an exceptionally hot day.
During hot weather a pond airpump can quickly increase oxygen levels and can be aworthwhile investment if your pond is well stocked.
If you wish to empty your pond and clean it out early summer is an ideal time to do it. A pond Vacuum is the ideal way to remove debris from the bottom of the pond. The fish are active and healthy, and the plants will respond well to being pruned.

Autumn
As the days start to shorten the fish will become less active, make sure they eat all the food as uneaten food can decompose and cause water quality problems. Once the water temperature drops below 10ºC (50ºF) switch to a wheatgerm food this is easily digested by the fish in cooler weather. You should also keep an eye out for any disease problems and treat promptly. As the water temperature gets lower the effectiveness of even the best medication is reduced.
As the plants start to die back Autumn is a good time to cut back the aquatic & marginal plants. Take care not to do this too early as many plants continue to grow right up until the first frosts. Some aquatic plants like Elodea will continue to grow very slowly right through
winter. It is best to cut these back and re-pot them to give them the best chances of survival through the coming winter. Keep the pond as free as possible of falling leaves from
surrounding trees as these can soon build up in the bottom of the pond and cause problems. You may wish to consider installing a pond net to catch the leaves, as well as protecting your increasingly sluggish fish from predators.
Before the onset of the really cold weather it is worthwhile changing 25% off the water,
remove as much of the sediment that has accumulated over the summer as is practical. If this is not removed fish may lie in this over winter causing health problems that may be difficult to rectify in cold weather. Pond pumps should be checked for wear & cleaned along with your
filtration system. If your pond has a UV clarifier this should be drained and stored in a frost free area to prevent damage caused by the expansion of freezing water.

Winter
As the days become short and the nights get cold you will notice the life in your pond becomes very sluggish. Check the water temperature with a pond thermometer, although the fish will sit on the bottom they will take small amounts of wheatgerm food on sunny days if the water
temperature is above 5ºC (40ºF). Below this temperature the fish are unlikely to feed as they enter a state similar to hibernation. If you choose to switch off your pump this should be
removed from the pond cleaned, dried & stored in a dry frost free area. If you have decided to leave the pump in the pond it should be left running, although fountains & waterfalls should not be used. Leaving them running will expose the slightly warmer pond water to cold air and chill the water further. The pump should be raised at least 15cm from the bottom of the pond this will trap a layer of slightly warmer water on the bottom where the fish will be living. In icy weather do not allow the entire pool surface to freeze. If ice covers the pond is can stop the water being
oxygenated and can allow a build up of toxic gases caused by decomposition. If the pond freezes over completely do not break the ice, the shock waves can harm or maybe even kill the fish. Instead stand a hot saucepan on the ice to melt a hole through it. Even better, is to prevent the pool freezing over completely. This can be achieved by the use of a pool heater or a polystyrene ice vent. Not only do these allow gaseous exchange, but they can also help reduce the pressure on the sides of the pond caused by the expanding ice.