15 Gallon Standard
A fantastic, often overlooked size that provides a two-foot swimming lane for active nano fish without the height of a 20-gallon.
Similar Tanks & Sizes
A fantastic, often overlooked size that provides a two-foot swimming lane for active nano fish without the height of a 20-gallon. With a capacity of 57 litres (15 gallons) and dimensions of 61 x 30 x 30, this standard tank is compatible with 76 species in our database — giving you plenty of options for a thriving community setup.
Tank equipment picks
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Stocking Tips
- 💡Choose one centrepiece fish and build your community around it. Avoid multiple territorial species in a tank this size.
- 💡A good filtration system rated for 1.5× your tank volume helps maintain stable water quality.
Stocking Recipes
Pre-built species combinations that work well together in this tank.
Peaceful Community
- Apistogramma Resticulosa Mamor×1Centerpiece
- Chili Rasbora×6Schooling
- Bee Shrimp×5Bottom Dweller
Bold & Beautiful
- Black Ocellatus×1Centerpiece
- Dwarf Molly×6Schooling
- Apistogramma borellii (Umbrella Cichlid)×1Bottom Dweller
Nano-Friendly Mix
- Chili Rasbora×6Schooling
- Bladder Snail (Pest Snail)×1Bottom Dweller
Gentle Giants
- Black Skirt Tetra×1Centerpiece
- Dusky Millions Fish×5Schooling
- Apistogramma borellii (Umbrella Cichlid)×1Bottom Dweller
Low Maintenance Setup
- Chili Rasbora×6Schooling
- Bee Shrimp (Crystal Red / Black)×10Bottom Dweller
Schooling Showcase
- Chili Rasbora×6Schooling
- Blue Pearl Shrimp×6Bottom Dweller
Water and maintenance products
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Commonly Mis-Stocked
These fish are frequently added to this tank but may outgrow it or cause problems. Proceed with caution.
Amazon Puffer requires at least 75cm of swimming length, which is 23% longer than this tank's 61cm.
American Grass Shrimp fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Arrowhead Puffer requires at least 75cm of swimming length, which is 23% longer than this tank's 61cm.
Bladder Snail (Pest Snail) fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Blue Pearl Shrimp fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Cherry Shrimp fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Convict Cichlid requires at least 75cm of swimming length, which is 23% longer than this tank's 61cm.
Dusky Millions Fish fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Dwarf Molly fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Emerald Green Cory requires at least 75cm of swimming length, which is 23% longer than this tank's 61cm.
Endler's Livebearer fits this tank now but grows rapidly — monitor closely and be prepared to upgrade.
Fairy Cichlid (Brichardi) requires at least 75cm of swimming length, which is 23% longer than this tank's 61cm.
Centerpiece Fish
Bold, eye-catching species that serve as the focal point of your tank. Typically kept singly or in pairs.
Apistogramma Resticulosa Mamor
Apistogramma cf. resticulosa Mamor
The Apistogramma cf. resticulosa 'Mamor' is a peaceful but territorial dwarf cichlid originating from the Mamoré River basin in South America. Known as the 'Thin-line Dwarf Cichlid', they require soft, sandy substrates for sifting and complex environments with driftwood and leaf litter to establish territories. While generally peaceful in community tanks, they become highly aggressive during spawning and will hunt dwarf shrimp.
Apistogramma elizabethae
Apistogramma elizabethae
A rare and highly sought-after dwarf cichlid native to the extremely acidic blackwaters of the Rio Uaupés basin in Brazil. Known for its spectacular finnage and sensitivity to water parameters. They require pristine, very soft, and acidic water, alongside a fine sand substrate for sifting.
Barlow's Dwarf Cichlid (Apistogramma Maulbrüter)
Apistogramma barlowi
A unique South American dwarf cichlid officially described as Apistogramma barlowi (2008), but widely known in the hobby by its trade name 'Maulbrüter' (German for mouthbrooder). Unlike most Apistogramma species which exclusively spawn in caves, this species is a facultative, biparental mouthbrooder. They thrive in soft, acidic water and require fine sandy substrates.
Betta (Siamese Fighting Fish)
Betta splendens
The Siamese Fighting Fish is an aquarium icon known for its labyrinth organ (allowing air breathing) and vivid colors. While hardy, they require heated, filtered water (24-30°C). Males are solitary and fiercely territorial. Females are generally less ornate but can be kept in 'sororities' with strict precautions (minimum 5 females in 75L+).
Betta Smaragdina
Betta smaragdina
A beautiful wild-type Betta species native to the Khorat Plateau of Thailand, known for its striking iridescent emerald-green scales. Unlike the domestic Betta splendens, they are slightly more peaceful and closely resemble their natural wild form. They are excellent jumpers and require tight-fitting lids.
Black Ocellatus
Lamprologus speciosus
The Black Ocellatus is a highly entertaining and fiercely territorial shell-dwelling cichlid from Lake Tanganyika. Despite their tiny size, they have a massive personality and will vigorously defend their chosen snail shell from fish much larger than themselves. They require a sandy substrate to bury their shells and hard, alkaline water to thrive.
Schooling Fish
Active swimmers best kept in groups. They bring movement and colour to the mid and upper levels of your tank.
Black Neon Tetra
Hyphessobrycon herbertaxelrodi
A peaceful, active schooling fish native to the Paraguay basin. Known for its striking contrast of a dark black lateral stripe underneath a glowing iridescent white/green-gold stripe. Excellent for community aquariums, particularly in planted setups or blackwater biotope tanks with subdued lighting.
Blue Back Blue Eye
Pseudomugil cyanodorsalis
A tiny, highly active euryhaline species native to the mangrove swamps and tidal estuaries of Northern Australia. While biologically capable of surviving in pure freshwater or full marine conditions, they require a brackish aquarium (SG 1.005-1.015) to thrive, breed, and resist disease long-term. They are peaceful shoaling fish but spectacular jumpers, so a tight-fitting lid is absolutely mandatory.
Cardinal Tetra
Paracheirodon axelrodi
A stunning schooling fish native to the upper Orinoco and Rio Negro basins in South America. Famous for its brilliant iridescent blue line and a vivid red stripe that extends the full length of its body (distinguishing it from the Neon Tetra). They are strictly schooling fish that thrive in warm, acidic blackwater environments.
Cherry Spot Rasbora
Rasbora rubrodorsalis
A peaceful and active nano cyprinid native to the slow-moving, heavily vegetated waters of the Mekong basin in Southeast Asia. It is characterized by a distinctive bright red spot on its dorsal fin and a dark lateral line. They are a somewhat shy but excellent shoaling species that thrives in blackwater or heavily planted setups.
Chili Rasbora
Boraras brigittae
A striking, deeply red nano fish native to the blackwater streams and peat swamps of southern Borneo. They are extremely peaceful and require a mature, densely planted aquarium with soft, acidic water. Due to their tiny size, they are completely safe with adult dwarf shrimp and are ideal for nano setups.
Clown Killifish
Epiplatys annulatus
A striking nano killifish resembling a tiny rocket. Native to West African swamps, they have distinct black and yellow vertical bands. They are strictly surface dwellers (top-level) and are non-annual, meaning they live longer than annual killifish (2-3+ years). They are notorious jumpers and require a tight lid.
Show 17 more schooling fish
Bottom Dwellers
Species that inhabit the lower reaches of the aquarium, helping keep the substrate clean and adding activity to the tank floor.
African Dwarf Frog
Hymenochirus boettgeri
A fully aquatic amphibian that is peaceful and highly entertaining. They possess lungs and must regularly dart to the surface to breathe air, so tank height should ideally be under 40cm (15 inches). Due to their poor eyesight, they hunt by smell and tactile vibration, making them slow feeders that can easily starve if housed with fast, aggressive fish. They are social creatures that thrive in small groups.
Amano Shrimp
Caridina multidentata
A highly popular, industrious freshwater shrimp renowned for its unmatched algae-eating abilities. Popularized by aquascaper Takashi Amano, they are significantly larger and hardier than most dwarf shrimp (like Cherry Shrimp). They are notorious food-thieves during feeding time and excellent escape artists, requiring a tight-fitting lid. Their larvae require saltwater to develop, so they will not overpopulate in a freshwater aquarium.
American Grass Shrimp
Palaemonetes kadiakensis
A completely freshwater shrimp native to North America. Often sold interchangeably with Ghost Shrimp (P. paludosus), the American Grass Shrimp is hardier, breeds more easily in entirely freshwater, and is an excellent, active scavenger for community tanks. They have a completely transparent body and prefer planted aquariums.
Apistogramma borellii (Umbrella Cichlid)
Apistogramma borellii
A hardy and relatively peaceful dwarf cichlid native to the Paraguay River basin. Uniquely among Apistogramma, they tolerate cooler (sub-tropical) water temperatures. They are excellent for planted community tanks but require sandy substrates to sift and leaf litter or caves to establish territories.
Assassin Snail
Anentome helena
A highly effective and popular carnivorous freshwater snail used primarily for pest snail control. They actively hunt and consume smaller snails like bladder, ramshorn, and pond snails. Featuring a striking yellow and dark brown spiraled shell, they are a functional and attractive addition to aquariums. Unlike many aquatic snails, they are not hermaphroditic and reproduce quite slowly.
Bee Shrimp
Caridina logemanni
A highly prized dwarf freshwater shrimp known for its striking opaque color bands. Native to streams in Southern China, they require specific parameters to thrive: cool, highly oxygenated, acidic, and very soft water. This is usually achieved using RO (Reverse Osmosis) water remineralized with specific shrimp salts and active buffering soil. They are highly sensitive to nitrogen spikes and copper, and are extremely vulnerable to fish predation.
Show 28 more bottom dwellers
Other Compatible Species
Additional species that are compatible with this tank size but don't fall neatly into the categories above.
Betta Imbellis
Betta imbellis
Known as the 'Peaceful Betta', Betta imbellis is a wild species closely related to Betta splendens. Unlike their highly aggressive domestic cousins, they can often be kept in pairs or carefully managed groups. They are native to blackwater swamps and require calm, tannin-stained water with plenty of cover. They are exceptionally prone to jumping.
Endler's Livebearer
Poecilia wingei
A tiny, vibrant, and highly active livebearer closely related to the Guppy. Males display intense, neon colors and patterns, while females are larger and plainly colored. They are prolific breeders and require hard, alkaline water to thrive.
Guppy
Poecilia reticulata
One of the most iconic and widely kept aquarium fish. Renowned for their incredible colors, hardiness, and prolific breeding. As livebearers, they give birth to fully formed, free-swimming fry. Males constantly pursue females for mating; therefore, a ratio of at least 2 females per male is strongly recommended to disperse stress.
Honey Gourami
Trichogaster chuna
The smallest and most peaceful member of the Trichogaster genus. Ideally suited for planted nano aquariums. Unlike the aggressive Dwarf Gourami (*T. lalius*), Honey Gouramis are timid and gentle. True Honey Gouramis rarely exceed 5cm. Note: Many bright red fish sold as 'Red Honey' or 'Red Robin' are actually Thick-lipped Gouramis (*T. labiosa*), which grow larger.
Platy
Xiphophorus maculatus
A quintessential community fish known for its durability and massive variety of colors. Native to Central America, Platies are livebearers, meaning they give birth to free-swimming fry. They are peaceful, active grazers that require hard, alkaline water to thrive. They are excellent for beginners but breed prolifically.
Frequently Asked Questions — 15 Gallon Standard
How many fish can I put in a 15 Gallon Standard?
The 15 Gallon Standard (57 L / 15 gal) is compatible with 76 species in our database. The actual number of individual fish depends on the species mix — use the stocking recipes above as a starting point and aim to keep the total bioload below 85% of capacity.
What is the best centrepiece fish for a 15 Gallon Standard?
Popular centrepiece options for this tank include Apistogramma Resticulosa Mamor, Apistogramma elizabethae, Barlow's Dwarf Cichlid (Apistogramma Maulbrüter). A centrepiece fish should be the focal point of your aquarium — choose one with colours and behaviour that complement your other species.
What schooling fish work in a 15 Gallon Standard?
Great schooling options include Black Neon Tetra, Blue Back Blue Eye, Cardinal Tetra. Schooling fish should be kept in groups of at least 6 to encourage natural behaviour and reduce stress.
What bottom dwellers suit a 15 Gallon Standard?
Suitable bottom dwellers include African Dwarf Frog, Amano Shrimp, American Grass Shrimp. These species occupy the lower zone of your tank, helping to keep the substrate tidy and adding activity to an often-overlooked area.
What temperature should a 15 Gallon Standard be?
The ideal temperature depends on the species you keep. Most tropical freshwater fish thrive between 24–27°C (75–80°F). Check each species' requirements and aim for the overlapping range that suits all your inhabitants.