Carassius auratus in a fish pond - Colouration

The Carassius auratus species is commonly kept in fish ponds perhaps because it's a cheap fish that's widely available. Often these fish are red, however young specimens may be even black, gray or a mix of all of these colours. Inexperienced fishkeepers usually cannot explain why adult fish (bought from pet store or Goldfish breeders) are coloured nicely while their babies' colours (Goldfish are very easy to breed no matter whether kept in aquariums or ponds) lack.

Mainly lack of colouration can be explained via food. Food is very important for every fish, some species won't develop colouration - thus it's good to purchase specialised food for Goldfish, although they'll also eat insects from water surface (assuming you keep them in ponds).

Goldfish specimens can restore their colouration in a couple of months if they're fed properly. Another reason why your fish' colouration lacks is poor water. Water in a fish ponds should be tested and eventually changed if it's not satisfactory. The trick is to perform tests each week or once every other week in order to ensure that it's still of good quality.

Goldfish aren't very demanding, thus pH of 7 is just fine, water temperature can be as low as 0°C (for fish kept in ponds - during Winter), however high temperatures such as 30°C won't bring any benefit to your Goldfish. Ideal range of general water hardness is 8-12. A pond that holds 3000 liters of water can easily house 40 specimens, however they produce lots of waste and thus overcrowding is not recommended no matter how big your pond is!

If you keep conditions stable, if you keep water properly mineralised, your Carassius auratus will show beautiful colours. Low mineralised waters often cause lack of bright colours and fish stay dark.

If you want to read more about this popular species, here are pages that are worth a visit!

Carassius auratus @ http://animaldiversity.ummz.umich.edu/site/accounts/information/Carassius_auratus.html

Carassius auratus auratus @ fishbase.org

Goldfish Types @ animal-world.com

Carassius auratus @ bio.txstate.edu

Goldfish @ fl.biology.usgs.gov

Carassius auratus auratus @ aqua-fish.net (this belongs to us)