How can I breed goldfish in my aquarium?


Is it possible to breed goldfish in an indoor aquarium? Paul Green of the Ranchu Brotherhood and the Goldfish Society of Great Britain explains how it's done.

You can breed goldfish in an aquarium quite easily and many breeders remove their chosen pair or trio (one female and two males) of fancies from their tub or pond and transfer them to a prepared tank.

The equipment required is fairly basic and I would use: a tank of 136 l/30 gal because as the eggs hatch water quality can quickly suffer, a heater set at 20°C/68°F, spawning mops or equivalent, methelyne blue to prevent fungus spreading from unfertilised to fertilised eggs, an air pump and small net.

You will also need food for the babies, such as freshly hatched brineshrimp or some off-the-shelf fry foods. Employ some air/sponge filtration too as it can be difficult doing large water changes with so many babies around!

Remove your parents from the tank as soon as spawning is over because the eggs are adhesive and can’t be moved — and they will be eaten by the parents or other tank mates. This explains why spawnings in goldfish community tanks often don’t work out.

The eggs should hatch in four days and the fry will become free swimming in another 24 hours.That’s when feeding begins.

When choosing fish to breed with they should be the best examples of their type you can find. Get more information on this subject from the Goldfish Society of Great Britain, details of which are available on

This item was first published in the October 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.