While guppies are peaceful fish who can thrive in a community tank, you must choose the right tankmates for them. As tropical fish, guppies need to be kept in water between 66 and 84 degrees Fahrenheit, so their companions must require similar conditions. Avoid known fin-nippers, such as tiger barbs or bumblebee gobies, and fish who grow too big, such as large mollies, platies or swordtails. Small, peaceful fish are the best tankmates for guppies.
Guppies are schooling fish, so they should be kept with others of their own kind. A lone guppy is likely to become shy and nervous, and will spend all his time hiding out in plants or behind rocks. They're best kept in groups of three males and five to six females. However, if you don't want them to breed, keep a single-sex group of six or more individuals. Males kept without females may show some aggression toward each other, but this is usually only minor.
The name cory catfish refers to any of the 150 catfish species belonging to the taxonomic family Corydoras. Known to be extremely placid, these fish are also easy to care for and ideal for beginner fishkeepers. As bottom-feeders, they'll add some diversity to a community tank where most species stick to the middle or the top of the aquarium. Popular species include peppered, bronze and panda cories. They need to be kept in groups of six or more to keep them happy and stress-free.
Brightly colored tetras make a welcome addition to a community tank, but only the smaller species are suitable to be kept with guppies. Avoid red minor and Buenos Aires tetras, as they can be prolific fin-nippers. Neon, loreto, glowlight, coffee bean, emperor, cardinal and ember tetras are all small and peaceful. Happiest in large schools, tetras should be kept in groups with a minimum of six of their own kind, but preferably more.
Most other small, peaceful fish can be kept with guppies. You could keep some interesting, translucent glass fish or a school of white cloud minnows. Honey gourami, plecos and harlequin rasboras are other fish options. If you want a change from fish, tiny ghost shrimp will get along with your guppies, and have the added benefit of being excellent tank cleaners.
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