Caring for goldfish is easy once you learn just what to do. Goldfish require much more care than most of us have been led to believe. They cannot live in bowls; they need a lot of space to grow. The perfect home for a goldfish is a pond, but since this may not be a practical solution; most of us keep our goldfish indoors in tanks and aquariums. If you want your goldie to live a long healthy life, learn the basics to goldfish care. Goldfish aquariums need filtration and surface action; your goldfish home must have completed the nitrogen cycle in order for the water to be safe or carbon must be used in a filter to absorb ammonia. Many goldfish will be poisoned by ammonia, which is produced mostly by decaying food and fish pooh. If ammonia is present; beneficial bacteria form to feed on it. These friendly bugs make the conversions for us. We call this process the nitrogen cycle.
Goldfish require cooler and heavily oxygenated water.
Goldfish spend most of their time on the bottom of the tank, searching for food or hovering just off the bottom, resting. If you see them at the surface; this may be sign there isn't enough oxygen in your tank water.
Most new goldfish die from ammonia poisoning or they suffocate; don't let this happen to your fish.