Goldfish are a popular pond fish because they’re small, inexpensive and colourful.
They’re also extrememly hardy and can survive for brief periods of time in a pond covered in ice.
Common goldfish, including the comet and sometimes fantail varieties can be kept in a pond all year round in temperate and subtropical climates.
Goldfish enjoy a range of different pond sizes, but the depth should be at least 80 cm (30 in) to avoid completely freezing over.
Keeping ponds healthy
A filter is important for keeping the pond clean and clearing waste. Plants are essential as they contribute to the filtration system and act as a food source for the fish. Plants also raise oxygen levels in the water.
Common goldfish are cheap and low maintenance but are prone to disease, which can be caused by excessively dirty water, overfeeding or overcrowding.
An illness can quickly become fatal, meaning rapid treatment is extremely important.
Several symptoms that can indicate a sick fish include:
- cuts on any of the fins
- a change in scale or eye colour
- excretions from the nose
- scales falling off
- odd-coloured marks on the fish
- fish frequently making trips to the surface.
