Information on Fry

This page is to be dedicated to information most ponders want to know. I am going to try and cover some things that I found very difficult to find on the Web or in books without extensive research. I hope this page will become a useful tool for those who come here. Please let me know if you find it helpful or if there is something you would like to see.

One of the things I wanted to see was a picture of a fish egg. Having never had fish breed in my tanks, when I put them in the pond, they spawned freely and I had no idea what I was looking for. I also wanted to know how long it took for the eggs to hatch and once they did, what did the fry look like. So, below are pictures of goldfish eggs and the stages the fry go through before they become recognizable fish.

This is a three day old embryo developing inside the goldfish egg.

These are four day old embryos still attached to the waterplant.

And below is a newly hatched goldfish one hour old.

This is a nine day old goldfish, including the 5 days as an egg and 4 days as a fry.

Goldfish eggs normally hatch in four to five days at a water temperature of 68 degrees. It is possible to distinguish between fertile and infertile the day after spawning. Fertile eggs, which can very from pale amber to a pale yellow will remain clear, unfertilized eggs will be opaque. After the egg hatch it then takes another few days for the fry to become freeswimming. Sudden drops in temperature can delay the hatching of the eggs for several days. It if gets cold enough the young fish can die or become severely weakened that proper development never occurs. Goldfish eggs require more oxygen in comparison to volume, therefore mud or organic debris is not suitable for egg development as this will use up needed oxygen. Eggs hatched in water deeper than 12 inches usually ends in the death of the fry. Fry hatched one week will eat newly hatching fry and the mature fish will eat the fry if left to develop in the pond.