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The Goldfish Gazette, Issue #027 -- Culling Fry To Produce Champions
March 31, 2016

Goldfish Care Tips and Guidelines

A Free Monthly Resource For Goldfish Enthusiasts
March 2016
Issue #027

In This Issue
Culling fry to produce champions

The process of producing champion Goldfish, or at least very high quality fish doesn't stop after the first cull.
Some fancy varieties often take years to develop their characteristics (such as Lionheads), and during this time they must be kept in the very best conditions.

Culling Fry To Produce Champions

I have covered this topic twice before, in issue 9 and 12 because it is important to realize that once you start becoming successful at breeding goldfish, you then create the problem of handling huge numbers of fish.

It is easy for a week or two to manage several thousand fry, but after that feeding and space quickly become major issues.

Reasons To Breed Goldfish

You need to be clear why you want to breed your Goldfish. Is it for:

  1. The challenge
  2. Replacing existing fish
  3. Improving the quality of your fish
  4. Making money
  5. All of the above.
For many, the challenge of breeding Goldfish is so great they are not too concerned about what varieties they are breeding together, as long as they produce a successful spawn.
This usually results in a spawn of mixed varieties that does nothing to improve the quality of their fish that have taken hundreds of years to develop.

Most serious breeders are always looking for perfection, and realize their current breeding stock will be past their prime after a few years so will need replacing, hopefully with higher quality fish.

To make money from Goldfish you need a commercial setup, a topic for another day, so at best you could make some money selling off fry to others who will grow them on, and by selling juveniles surplus to your requirements.

Because most of us have limited resources (space) to grow our Goldfish, I will concentrate on the problems relating to raising fry to replace ageing fish and/or improving the quality of our fish.

Culling Heavily and Often

I won’t repeat the process of culling again because it is well covered in issues 9 and 12. What I want to emphasize in this issue is the amount of space required to raise just a few fry for their first year.

If you look at the two images above, one shows Black Moor fry at 1 week old, and the same fry at 7 weeks. At this age they had an average body length of 7/8 inch (22mm).

To achieve this growth rate the 12 fry had all the food they could eat, very clean water and space.

The 7 week old fry were in a 65 liter aquarium, and had been culled down from a spawn of 1,300 fry. By 16 weeks there were only 4 fish in the aquarium with a body length of 2 3/16 inches (55 mm). The amount of live food the rapidly growing fry ate was huge, and so was the waste they produced. Large water changes were made several times a week.

If one 65 liter aquarium supported 4 55 mm fry, to raise the entire brood I would have needed 325 aquariums or 21,000 liters (with heavy filtration).

The 4 juveniles didn’t seem to want to grow much over 70mm in the 65 liter aquarium and were moved outside in the spring to an 80 gallon (300 liter) pond. A pond of this size (with filtration and water changes), will support about 8 adult Goldfish.

I hope you are you getting the idea that to raise even 4 fry to a reasonable size in 12 months requires a lot of dedication, food and space. To attempt to keep any more than this is beyond the resources of most enthusiasts, and as I have often repeated, all the fry will suffer if they are cramped and in poor water conditions.

Fancy Goldfish varieties such as Ranchu and Lionheads must be kept in the best possible conditions from the moment the eggs laid if they are to develop into champion fish.
If food or water quality is missing at any stage of their development, they will never develop to their full potential.

To learn more about Goldfish culling click here...

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 Feeding-long term test

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