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The Goldfish Gazette, Issue #014 -- Frustrations of Goldfish Breeding
February 27, 2015

Goldfish Care Tips and Guidelines

A Free Monthly Resource For Goldfish Enthusiasts
February 2015
Issue #014

In this issue
Frustrations of Goldfish Breeding
What's new on the Website

As your Goldfish fry grow and put on some size, they start to show faults that weren't there when you first selected them as your next generation parents.

Frustrations Of Goldfish Breeding

Goldfish breeding is a fascinating but often frustrating hobby.

This month I want to share the frustrating part.

Genetics and Regression

Goldfish of any variety want to regress back to the wild goldfish shape, color and finnage.

This regression tendency shows up when goldfish are bred.

By carefully selecting parents with the desired genetics, this tendency is suppressed to a large degree. We know some fry will still partially regress, but we hope that the majority of the fry will exhibit the parent's desired characteristics or even better them.

Caudal Fin Heredity

Some caudal fin characteristics can be quite accurately predicted when breeding goldfish.

If a long tailed goldfish is bred with a short tailed goldfish, the fry will all have medium length caudal fins.

If these fish are then bred together, they will produce fish with long, short and medium length tails (the second generation throw back factor is working here).

Paired Caudal Fin Heredity

When breeding goldfish varieties with paired caudal fins, you hope that a large number of fry will have paired caudal fins.

If the fry are growing well, at the end of the first week after hatching the caudal fins are quite evident, with single tailed individuals showing up quite clearly.

By the end of the second week the detail of the caudal fins is such that the amount of division (split) in the caudal fins shows up clearly. (Twin tail varieties should have divided caudal fins).

My recent spawn of Black Moor, with fish of unknown parentage produced about 1,300 fry.

Of these 65 had single or deformed caudal fins. This was about 5% which was a very good result. It showed the grandparents must have had excellent genetics.

But I did notice the number of fully divided caudal fins were few, no more than 4, with a further 125 or 10% having some division of their caudal fins and the rest none.

This number appeared low, but considering the female and one male has no division, one male is a tri-tail, and the other male has 75% division of his caudal, I was happy with the numbers as I only want 10 to grow to adults.

Caudal Fins Develop Into their Final Shape

After culling the fry down to 48, they have continued to grow quickly. As they have grown, their caudal fins have taken on their final shape and deportment.

This is where the frustration begins...

The images show 3 of the best juveniles that were selected for special treatment from the final 48 fry.

(For those with e-mail text readers that can't see the images, you will need to read the E-zine on the website back issues page.)

The image at the top shows a fish with nicely divided caudal fins, but they are different sizes and the top rays of the right caudal droop.

This fish won't make the final 10.

the next image again shows nicely divided caudal fins, but they are too wide. When swimming quickly this fish tends to shoot to the surface in a series of jerky movements.

Another reject.

The bottom image shows nice division, but the right hand caudal fin has grown out at an acute angle.

It won't be making the final 10 either.

This all proves that producing that champion fish isn't easy, but then if it wasn't a challenge we wouldn't do it would we?

To read more on how to cull Goldfish to produce champions click here...

What's New On The Website


You are the first to know.

I've finally created a Facebook page to compliment the website.

I will keep the page updated with current events that I won't be covering on the website.
At the moment I am uploading images of this season's Black Moor spawn that show the frys' first eight weeks of development.
Hop over and have a look at Be the first to add a comment before I add a direct link on the website.

Comments? Ideas? Feedback? I'd love to hear from you. Just reply to this e-zine and tell me what you think, or what topics you want covered.

Next Month's Topic

Goldfish medications and how to use them safely

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