The various options available to the pond keeper as the winter approaches fall into two main categories - continuation of filtration or removal of filtration. The decision is primarily determined by comparing the benefits of continuing filtration, which will help to sustain some degree of biological colony and reduce the risk of the pond freezing over, compared to the running cost and danger of low oxygen due to freezing. From a biological point of view, the continuation of filtration in a heated pond is essential. In an unheated pond, continuation will improve the speed of biological maturation at the beginning of the following season and give some protection in the event of winter warm spells.
If you decide to shut down the filter systems during the winter months, we would recommend the following:
- The system should be left to run for at least 2 weeks after feeding has stopped and should then be restarted approximately 3 weeks before feeding commences in the spring.
- Never feed your fish whilst the filter is out of operation.
- Once removed, the filter and UVC should be thoroughly cleaned with tap water and stored indoors.
- If removed, the pump should be cleaned and stored indoors. If the pump is a Prima it should be kept in a bucket of clean water to prevent the seals drying out and cracking.
- If the entire system is removed, we advise that a small pump is used to disturb the pond surface or a floating pool heater is installed. This is to try and prevent the pond from freezing over to allow oxygenation of the water.