I thought I would throw goldfish ponds into the mix, the reason being you can have any sort or size of pond and goldfish will be quite happy.
They will grow slowly to the size of their surroundings, will not destroy your plants, can adapt to cold and warm conditions and it is not uncommon for them to reach 20 years of age. These fish will give you years of companionship.
They will survive in very small ponds as long as the whole pond does not completely freeze and will also grow if their surroundings allow them - up to 40cm long.
Some serious fish keepers only keep goldfish and treat them as a speciality, just because they are such a hardy fish does not mean you should just automatically forget about them.
Goldfish are from the carp family and come in all types of colours and shapes. If you decide to have goldfish in your pond then please do not choose the moors goldfish, that's the ones with the big poppy out eyes, as they can get damaged in an outside pond.
Wildlife ponds and goldfish
If you have chosen a wildlife pond or have a wildlife pond which has no filtration system, then the only fish I would put into these ponds are wild goldfish or the common ones, unless it is a large wildlife pond then the doctor fish (tench) will adapt nicely.
Shorter bodied goldfish
One thing to take note of is that goldfish of the shorter body types like fantails, can become filled with gas due to temperature changes and swallowing too much air when feeding. This can make them look droopy and even float or swim upside down. Please do not mistake this for them being poorly as this will pass and they will recover.
If you are in an area that becomes very cold and you expect freezing conditions then stick with the common goldfish as the more fancy a goldfish the more they dislike cold conditions.
Please understand that not all goldfish are as hardy as the common goldfish......
Like many fishkeepers they buy a heater for thier goldfish ponds, they simply float on the surface and keep the water from dropping to a low temperature. They are very useful with all fish and I would certainly have one in most cold climates,you could even float a tennis ball in the pond,this stops it freezing over completely,unless the weather is really severe.
If you want a pond for decorative reasons and are not wanting to become a fish keeper then I would suggest goldfish are the perfect solution with low maintenance, pretty colours, shapes and are very hardy fish.
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