Water quality parameters for koi and gold fish

Selective breeding has produced a wide variety of goldfish and koi. However, koi color patterns have changed, while goldfish varieties have differences in their body shapes and fins. For example, ranchu and lion-head goldfish have colorful growths on their head that mane them appear different than other goldfish. The butterfly koi does have a longer tail fin, but other than this, most koi look like colorful carp. If you see a fish with unusual fins or appearance, it is probably a goldfish.

In this article, we look at the origins of both koi carp and goldfish and compare the two species.

Goldfish come in lots of varieties too. Fancies (ryukins, orandas, lionheads, etc) are not has hardy but are very cute. The hardy ones, like comets and shubunkins are inexpensive, hardier than koi and very colorful. Goldies can do well in shallower ponds. They need 50 gallons each.

Koi and goldfish ponds are ready for the spring/summer season.

Read on to find out more about the differences and similarities between koi carp and goldfish.
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How do I tell the difference between a koi & goldfish?

So when you look at a bag of food and the first ingredient is wheat, that's not the best choice for your fish. Wheat protein is not equal to fish protein. So keep looking. You should look for fish or aquacultural proteins as the first ingredient in a decent diet for your koi and goldfish.

To shop for Koi and Goldfish online, .


This is a typical hybrid between a koi and goldfish. This one shows a hybrid's typical distinctive trait which is the large hump behind the head. Not all hybrids have this hump, but most do. With qualities like these, I am surprised that they aren't a more popular pond fish, and breed for commercial sale. I have seen many backyard ponds in the 500 gallon size, and hybrids would be a great fish for those types of ponds. Another great application would be a water garden and lots of plants -- the hybrids get bigger than goldfish, but not huge like koi, and won't tear up the plants.
- Hybrids are sterile and can't reproduce.
- The hybrids I have experienced grow to 12" including the tail, and some up to 15" long.
- They seem to be tougher than koi and can take the lower water quality like goldfish can.
- Not sure on their life span (goldfish is about 10, koi is 60+).
- They also do not seem to attack plants like koi do.
The current record holder for the world's longest goldfish at the isn't actually a goldfish. It is a hybrid between goldfish and koi, as you can clearly seein the picture to the right. It is 18.7" long from overall including the tail fin.