What is the Smallest Fish in the World?

The tiniest fish in the world known in the 1990s are only one-half-inch long when they are fully grown.

They come from the waters of the Philippines and are the pygmy goby and the Luzon goby. Gobies like to live in waters close to shore. The waves would continuously knock them about unless they had a way to protect themselves. And they do.

On the forward part of their bodies, they have a suction cup that allows them to cling to an underwater rock while the waves pound around them. Most gobies are not so small as the Luzon and the pygmy.

They average between two and four inches in length and are among the most beautiful fish in the world.

The smallest fish known today is the Paedocypris fish. Is it only 7.9mm long and is found in swamps on Sumatra, Indonesia. Their habitat is currently threatened by land development used by farming.

The Paedocypris lives in very acidic waters with a pH of 3. This is very unusual and would make this fish very difficult to kept in captivity.