Instructions
Consider the size of potential tank mates. Many goldfish will attempt to eat their tank mates, regardless of compatibility, if the tank mate is small enough to swallow whole. Generally, common and fancy goldfish do well with other coldwater fish of the same size.
Choose a species that has care requirements that are similar to those of your goldfish.
Select a tank mate that does not require immaculate water. Goldfish are known for their excessive excrement products and their ability to stir up the bottoms of their tanks, which can be a disruption for tank mates that require clean environments.
Gauge the species' swimming speed. Common varieties of goldfish often move quickly to reach food and eagerly eat all they can, while fancy varieties of goldfish move at a slower pace. It is best to choose a species that can match the goldfish's swimming speed so as to ensure an even playing field at feeding time.
Select a tank mate that is not known to be aggressive. Goldfish can easily become moving targets for species that are attracted to their fins.
Let tank mates help maintain goldfish tanks. Some types of tank mates can help keep your goldfish tank clean. One bristlenose catfish can eat all the algae in a tank up to 50 gallons. Apple snails and butterfly loaches also control algae and eat goldfish food leftovers.
Visit a pet shop and buy your chosen goldfish tank mate.
Introduce the tank mate to its new goldfish buddy.
How to Buy Goldfish Tank Mates
Prevent your goldfish from being lonely by investing in some tank mates to keep your goldfish company. Whether your decision is based on attractiveness or practicality, your goldfish's tank mates are sure to earn their keep. Buy some goldfish tank mates and start the party in your aquarium.