Bizarre breed with bump on its head

Oranda are one of the most popular breeds of goldfish due to their bizarre looks

The growths on their heads, called wens, are benign but can cause vision problems. Luckily, wens can be trimmed by vets

In China, where goldfish were first domesticated 1,000 years ago, oranda have been nicknamed ‘flower of the water’ because of their large, fanning tail fins

Native to China and Japan, oranda are usually between five and seven inches long but can grow bigger. Common goldfish are normally longer, reaching more than eight inches long if put in a big enough tank

The world’s longest ever goldfish is believed to be one found in Holland in 2003, which was 18.7 inches

Despite widespread belief that goldfish have short lifespans, some breeds can live for 20 years. The oldest on record lived to 43

It is a myth goldfish have three-second memories. In fact they remember for months