Genetics of Calico Fantail Goldfish

I have always been fascinated with genetics. Although I am by no means an expert, breeding goldfish does have its benefits to see the affects of genetics. There are three categories of goldfish, metallic, matt and nacreous.

Nacreous Scaled Fantail Goldfish baby

Metallic: These fish have a lot of guanine present. Their scales are highly reflective and they look like metal in the sunlight. Metallic goldfish have two dominant genes, lets say SS.

Matt: These fish appear to have translucent or flat coloured scales. There is no reflective colouration. Matt goldfish, which are white and lack colour have to recessive genes, lets say ss.

Nacreous: This is a fish with a mix of translucent and reflective scales. Nacreous goldfish have the genes, Ss.

Most calico goldfish are nacreous goldfish, they have undertones of colour in their skin under the translucent scales and other colours in the reflective scales.

In the recent breeding, I spawned two nacreous goldfish. The resulting fry by these predictions should be as follows:

               S              s


S           SS              Ss


s            Ss              ss

This means there is a 25% chance of metallic goldfish, 25% chance of matt goldfish, and 50% chance of nacreous goldfish.

In my spawning, 60% are nacreous goldfish and 40% are matt goldfish. Now these numbers are different than predicted, but considering the fact that I selected only the two-tailed fry, these numbers are possible.

I have not yet considered the affects of colour, but from looking at the nacreous goldfish babies, they seem to be an even split between the parents.

Now, matt goldfish tend to be less impervious to cold weather, I hope they last the winter, since they are very beautiful babies.

Baby Fantail Update

So it has been a few weeks since I took a picture of the babies. I decided to catch a few to see how they are doing. Here are the photos of them now. The water is very cold, so I have stopped feeding them for winter.

This little guy has such a cute little patch over his eye. And his calico patterns are so cool. He even has a little bit of blue like his mother.

This little pinkie has a lovely tail with a nice spread.

This little guy has a lovely long tail and has very nice fantail proportions.

The Parents

I thought I would add a little bit about the parents of these babies and a little bit about how I raised them. This is the mother of the baby goldfish I showed in the May 2015 spawning. This is quite an old photo from 2011. She has grown quite a lot since then.

I chose to spawn the blue calico female with a red calico male. Sadly I do not have a picture of him yet. I placed both her and him in a separate section of the pond with plants for her to lay her eggs on.

Here is a picture of a spawning I did in 2011 with two other fantails. They produced lovely babies (below is a picture of one). It was an even split of red and white and red calico fantail goldfish. 

The red calico is the female and the red and white fantail is the male. This was only a temporary 60 gallon container I made for them to spawn in.

Here is one of their babies in the bigger pond at around 4 months using an underwater camera.

In the recent spawning, I sectioned off a part of the pond for the two goldfish. I only collected some of the eggs as I did not want a lot of baby fantails. I raised the young in a nursery pond of 60 gallons and fed them dried brine shrimp. I had an air stone and I did frequent water changes. At one month, I kept 9 babies in the 60 gallon nursery pond and put the other babies with single tails or deformities back in the big pond with the other goldfish. 

Here is a picture of one of the babies at 3 weeks. Already I can see some colour change.

Here is a picture of two of the babies at almost 2 months. They are just starting to get their colours. 

At around 3 months, the fantail babies were big enough to enter the big pond with the parents, although I moved all the comet and common goldfish out of the pond to eliminate aggression towards the young fantail goldfish.

So far, the babies are doing great and I hope they will do well over the winter.

May 2015 Fantail Spawning

Back in May I decided to spawn a female blue calico fantail goldfish with a red male calico fantail goldfish. Below are some of the offspring of these two fantails. These pictures show the babies at around 3 months. All the babies are 1 to 2 inches long and living happily in the big pond with their parents as they soon will be preparing for winter.

I have a couple pinkies. Its quite cool having some white fantails in the pond.

This one is the only one with a little bit of a blue tail.

This little baby does have a nice tail, but I failed to take a decent picture of him.

I am excited to see how these guys turn out by next summer. It has been fun watching them grow in their nursery pond and develop some unique colours. They have grown and changed slightly in colour since I took these pictures.