Goldfish should NOT be kept in little bowls. They produce a huge amount of waste for their size and so they need a very powerful filtration system. Pet shop workers will tell you they grow to fit the size of their tank. This is not true – if the tank isn’t big enough for them, they die young. With enough space and decent filtration, a goldfish can live for decades.

All the rubbish you hear in some pet shops is just because they know they’ll sell a lot less fish if you actually knew what it takes to look after them.