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FISH / health & care

How Do I Set Up My Aquarium for Multiple Fish?

Be sure they all have similar temperaments & need the same water chemistry, temperature & diet.

African cichlids

1. African cichlids

These active fish can be territorial and aggressive, but actually do better when crowded because the aggression is spread throughout the community. Monitor them closely and remove fish that become too aggressive. The aquarium should be at least 4’ long. Diets vary greatly, so find cichlids with similar diets.

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South American cichlids

2. South & Central American cichlids

These fish vary greatly, so choose ones with similar size, diet and temperament. Larger varieties can be very aggressive and should not be overcrowded. Choose a tank size suitable to the fish as an adult. Always pay close attention and remove fish if they become too aggressive.

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3. Goldfish

Goldfish are laid-back, easygoing and hardy; they can live up to 20 years.They should only be kept with other goldfish because of their unique diet and, unlike other tropical fish, do not need a heater. Because they produce a lot of waste, pay close attention to their water quality. You should have 20 gallons of water per goldfish.

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Community fish

4. Community fish

These active fish are compatible with other non-aggressive species of fish. Schooling species do best in quantities of five or more.

Semi-aggressive tropical fish

5. Semi-aggressive fish

As their name suggests, these may bully smaller tank-mates, so aim for an aquarium of fish all close to the same size. Aggressive fish should always be monitored closely to ensure that they are getting along. Fish that become too aggressive should be removed.

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