Have you ever thought about adding an aquarium to your home? They can be a fantastic addition to any household or worksp ...

Freshwater lakes and ponds are ... You have to introduce it, and that's where a lot of goldfish owners slip up because you can't just buy a fish the same day you get your tank.

There are some species-specific issues regarding anesthesia concentrations (some species like eels may require more and other species less) but in general it's very similar to freshwater fish surgery.

This genetic condition is more common in freshwater aquarium fish species, such as goldfish. Fish with polycystic kidney ...

It won grand champion at the All Japan Koi Show in 2017, and is the most expensive koi fish ever sold. Koi may just look like an oversized goldfish, but they're not even remotely related.

Scientists have decoded the secrets behind a goldfish's ability to survive in ice-covered lakes. They've worked out how and why the fish turn lactic acid in their bodies into alcohol, as a means ...

This story appears in the April 2017 issue of National Geographic magazine. Hundreds of millions of people worldwide would lack their prime source of protein without freshwater fish. Yet the lakes ...

A report has warned of a "catastrophic" decline in freshwater fish, with nearly a third threatened by extinction. Conservation groups said 80 species were known to have gone extinct, 16 in the ...