What is a Calico Goldfish? – Hint: It is all about the scales

Goldfish would not have existed if it is not for their bright and variation of colors. Most of the goldfish breeds come in solid colors such as red, orange, yellow, blue, chocolate, white and black; or in bi-colored of red/white or black/white; or in tri-colored and calico. My favorite… the calico variety.

So what is a calico goldfish?

To me, a calico goldfish is like a dirty goldfish. Seriously, it looks as if you have taken a white goldfish with a tint of blue, and smeared it with some black dirt, colors and glitter, and the result is… OH SO PRETTY!

What Is A Calico Goldfish?

Well, of course that is not how a calico goldfish comes about. That would be pure fish abuse!!!

Calico goldfish got its dirty good looks from its scales.

Goldfish Scales

Scales are protective plates that are developed on top of the goldfish skin. The scales grow in an overlapping pattern like the shingles on a roof. Besides protecting what’s underneath (i.e. the skin), the scales also function as reflectors of the coloration on the dermis, which is a layer of the skin.

So different scale types cause different coloration variations on our goldfish.

Fish Scales

There are 3 types of goldfish scales:

  1. Metallic
  2. Matt
  3. Nacreous

1. Metallic Scales

Metallic scales are coated with guanine, which is a layer of pigment that refracts light. This layer of guanine is at the underside of the scale. This gives them a shiny metallic appearance. So basically any color pigment on the dermis will be enhanced into a shiny version of the color by this type of scales.

So red will be shown as shiny red, orange will be shown as shiny orange, no color pigment will be shown as shiny white or silver and yaddi-yadda… get the point?

Ranchu with Metallic Scales
My Ranchu goldfish with shiny metallic scales

Goldfish with metallic scales are easier to find. They are usually available in one solid color of red or yellow, or bi-colored of red/white. Black on these metallic scales usually is just temporary as the goldfish goes through color changes.

2. Matt Scales

You can think of matt scales as transparent or semi-transparent scales. Goldfish with matt scales look translucent or with flat coloration as the scales do not have any refractive function.

Oranda goldfish with matt scales
Oranda with mainly matt scales on the body

Young goldfish with this type of scales usually appear pink, not because they have the pink coloration but rather because the blood in their skin and tissues are shown through the transparent matt scales. As the goldfish grow, these scales get thicker and become less transparent.

Although goldfish with matt scales are available in some colors, these colors just appear flat and unattractive. So goldfish of this scales type are not so popular.

3. Nacreous Scales

We have arrived at the answer to the question “What is a calico goldfish?”. A calico goldfish is any goldfish breed that has this nacreous type of scales. So what are nacreous scales?

Nacreous or calico scales type is basically a hybrid of metallic, matt and a third scale type. Remember I mentioned that in metallic scales, the layer of the refractive pigment called guanine is at the underside of the scale?

Well, the third scale type here has the layer of guanine at the upper side of the scale, giving the clear scales a pearl-like shine.

Oranda Goldfish
Calico Oranda Goldfish

Goldfish with nacreous scales have the most colors combinations of red, orange, blue, black, white, etc as compared to goldfish with metallic or matt scales. They often have a bluish white background with patches of red, orange, grey and black scattered around the body and fins. Unlike the ones with metallic scales, the black in calico goldfish is more stable and permanent.

The color variations and the different scales effects all over its body are what gave the calico goldfish that dirty good looks.


The goldfish world started more than a thousand years ago when the Chinese people saw the color potentials from breeding the dull Prussian Carps. The selective breeding of goldfish continues from there to give us the varieties of goldfish that we see today.

Coloration is definitely one of the important factors that goldfish enthusiasts consider, and calico goldfish is right up there for this. It has many colors with some parts shiny, some parts not and some parts pearl-like.

Calico Telescope Goldfish
Photo by Benson Kua, CC BY

So what is a calico goldfish and why is it so colorful?

Well, the colors on a goldfish are very much shown through its scales. Different types of scales give a different kind of effects to a goldfish coloration. The 3 main scales types are metallic, matt and nacreous scales.

The nacreous scales type is the one that gives a goldfish splashes of different colorations all over the body and fins, and that is what makes a calico goldfish.

So now you know what is a calico goldfish and how it gets its dirty good looks. 🙂

Note: The following contains affiliate links. For more information, please visit my disclosure page.

Share this:

6 Replies to “What is a Calico Goldfish? – Hint: It is all about the scales

  1. This is a pretty awesome article! I had a few goldfish as a child and they all died. I did not really know how to take care of them. The fact that there are this many types is pretty cool. I really like goldfish and now I am thinking about going to get one. Thank you!

    1. Hi Patrick,
      With some knowledge and determination, keeping goldfish can get better. To me, goldfish are really interesting because of their varieties. They are like works of art. 🙂

  2. I like your post of the calico goldfish. It is easy to read. You explain the subject matter so well. this article grabs my attention and keeps it. I like your diagram and pics.

    1. Hi Latricia,
      Thanks so much for the visit and the comment. I hope my articles on goldfish and their care are helpful for fellow hobbyists.

  3. I am really glad I came across this site.
    My children raise goldfish by the dozens around here but never know there were such different kinds. Is it possible for a person that owns a home aquarium to breed goldfish well enough to get calico fish? How many generations do you think it would take? This sounds like it would be great family fun.
    We obviously know nothing about raising goldfish but we will stay in touch with your website to learn as we go.

    1. Hi Bob,
      Thanks for the comment. I do think it is possible to breed goldfish at home, but you will need to consider the additional spaces required for those baby goldfish (a lot of them!) to grow up. So if you can provide them that and proper care, yeah it’s fun! If not, then that may not be a good idea. If you breed 2 calico goldfish together, you may get around 50% of the offsprings calico also.

      If you are new to goldfish, do check out this post of mine:
      Taking Care of Goldfish for Beginners – 3 basic considerations to start off

      Hope that helps!

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.