Before buying fish, design your tank in three dimensions using alerts that warn when it's too full.

Tetras are small, colorful freshwater fish that are among the most popular choices for community aquariums. They are known for their peaceful nature, active swimming, and strong visual appeal in planted tanks.

Corydoras are small South American armored catfish prized for their peaceful nature, social behavior, and constant bottom-foraging activity. With more than 170 recognized species, they offer a wide variety of patterns and sizes while remaining one of the most popular groups for community aquariums.

Danios are active, hardy freshwater fish popular in home aquariums. Many species are well suited to community tanks and are especially valued for their constant movement and bold, energetic behaviour.

Livebearers are popular freshwater aquarium fish best known for giving birth to free-swimming fry instead of laying eggs. This hobby group includes familiar fish such as guppies, mollies, platies, and swordtails, which are valued for their colour, activity, and ease of care.

Angelfish are tall-bodied South American cichlids that have long been popular as centerpiece fish in planted aquariums. Their shape, finnage, and calm cruising behavior make them one of the most recognisable freshwater aquarium fish.

Bettas are labyrinth fish valued for their colour, finnage, and character. In the hobby, this group usually refers to Betta splendens and related species, which breathe atmospheric air and prefer calm, well-structured aquariums.

Cichlids are a highly diverse group of freshwater fish known for their intelligence, vivid colours, and complex breeding behaviour. The group includes everything from small dwarf species suited to peaceful community tanks to larger, more territorial fish that require specialised setups.

Discus are large South American cichlids prized for their round shape, colour, and graceful movement. They are considered one of the classic display fish for warm, peaceful softwater aquariums.

Dwarf cichlids are small cichlid species from groups such as Apistogramma, Mikrogeophagus, Laetacara, and Nanochromis. They are popular for combining classic cichlid behavior and colour with a size better suited to smaller aquariums.

Killifish are a diverse group of small egg-laying fish admired for their intense colours and unusual breeding strategies. The hobby includes both short-lived annual species and longer-lived non-annual species, so care requirements vary widely.

Rainbowfish are active, colourful schooling fish best known for their metallic sheen and display behaviour. Popular aquarium species come mainly from Australia, New Guinea, and nearby islands, and many make striking additions to spacious planted community tanks.

Rasboras are small, peaceful freshwater fish popular in community aquariums. In the hobby, this group includes several closely related Southeast Asian schooling fish known for their graceful movement, attractive colors, and suitability for planted tanks.

Gouramis are freshwater labyrinth fish known for their ability to breathe atmospheric air in addition to using their gills. Many species are popular aquarium fish thanks to their attractive colours, interesting behaviour, and suitability as display fish in planted community tanks.

Plecos are loricariid suckermouth catfish that range from small community species to very large aquarium fish. Many are valued for their unusual shapes, armour plating, and rasping mouthparts, but care requirements vary enormously by species.

Freshwater shrimp are popular in planted and nano aquariums for their colour, behaviour, and algae-grazing habits. The hobby ranges from hardy Neocaridina types to more demanding Caridina species that need softer, more stable water.

Freshwater snails are common in aquariums as algae grazers, detritus cleaners, and interesting invertebrate display animals. Species vary from small pest-type ramshorns to larger ornamental types such as nerites and mystery snails.

Barbs are active freshwater fish popular in home aquariums for their movement, colour, and variety. In the hobby, this group includes many cyprinid species ranging from peaceful community fish to more boisterous types such as the Tiger Barb.

Catfish are a broad and diverse group of freshwater fish recognised by their barbels and bottom-oriented feeding habits. In the hobby, this catch-all category includes peaceful community fish as well as larger nocturnal or predatory species.

In the freshwater hobby, “shark” usually refers to several torpedo-shaped cyprinids such as bala sharks, rainbow sharks, and red-tailed black sharks. These fish are popular for their bold shape and movement, but they vary greatly in size and temperament.

Loaches are a diverse group of bottom-dwelling freshwater fish known for their unusual shapes, active foraging, and interesting behaviour. In the aquarium hobby, this category includes everything from shy kuhli-type loaches to larger, more boisterous species and specialist hillstream loaches.

Puffers are intelligent, characterful fish known for their beak-like teeth, curious behaviour, and species-specific care needs. The aquarium trade includes both freshwater and brackish species, ranging from small dwarf puffers to much larger solitary predators.

Gobies are a diverse group of small bottom-oriented fish that include freshwater, brackish, and specialist stream species. In the hobby they are valued for their character, perching behaviour, and unusual body shapes.

Oddballs are unusual freshwater aquarium fish that do not fit neatly into the common community categories. This browse group can include specialist predators, unusual bottom-dwellers, and niche species with highly specific care requirements.