How Many Comet Goldfish In A 20 Gallon Tank. And goldfish need a companion to stay active and healthy. How many fish can be kept in a 30 gallon tank?
For example, if you have a fish tank that is too cold, you may want to add a few drops of water to it to warm it up. This is quite a vast age range, but many factors determine how long goldfish will live in an aquarium environment. You need to allow a further 10 gallons for each additional fish.