Goldfish live in shoals, so they like the company of other goldfish. They enjoy swimming in and out of things so put something like the traditional shipwreck ornament in their tank. They also enjoy nibbling water plants so add some of these if your local pet shop stocks them. They enjoy nosing around in gravel so put some in the bottom of the tank. Use only aquarium gravel, never builder's gravel which may be poisonous to fish. The most important thing is to keep the water quality good with a filter and water changes every week. If the water quality is poor, they can’t get enough air to breathe. They become sluggish and the skin on their gills burns from the ammonia in the water.
