Freshwater fish
The list this site is actually built on.
Temperature, pH, adult size, and minimum tank for the freshwater species we use in stocking and compatibility. Not every fish in the trade — the ones people actually buy, including the ones they should not.
Each profile is adult size, a tank minimum we will not walk back, temperature, pH, diet, and what they actually do in the glass — algae, leftover food, or neither. Compatibility and stocking both read from this list. If a fish is missing, it is not in the math yet.
Start with a school or a bottom group, not eight species from the same rack. A 20 long is the default community. A 10 is one idea: betta, shrimp, or a nano school.
Skip
- Saltwater livestock — that page is empty on purpose.
- Anything the shop calls an algae eater without an adult size on the bag. Read the pleco profiles.
Run compatibility on the mix, then stocking with adult sizes.
Neon Tetra
Paracheirodon innesi
The default midwater school.
A group of six-plus fills the middle of a 20 long so the tank does not look empty.
Cardinal Tetra
Paracheirodon axelrodi
A showier neon that wants better water.
Same schooling job as neons, with a full-body red stripe.
Ember Tetra
Hyphessobrycon amandae
Nano school for a planted 10.
Actually fits a 10-gallon as a group.
Harlequin Rasbora
Trigonostigma heteromorpha
Calm midwater school for a 20 long.
Less nippy than barbs, less fragile than cardinals.
Zebra Danio
Danio rerio
Fast top-water school. Hardy, slightly chaotic.
Tolerates cooler rooms than tetras.
White Cloud Mountain Minnow
Tanichthys albonubes
The honest no-heater school.
Lives in the mid-60s without a heater if the room stays cool.
Guppy
Poecilia reticulata
Colorful livebearer. A population bomb if you mix sexes.
They pick leftover flakes and biofilm.
Endler's Livebearer
Poecilia wingei
A smaller, wilder guppy.
Grazes biofilm in planted nanos.
Platy
Xiphophorus maculatus
Sturdy livebearer for hard tap water.
Grazes a bit of algae and leftover food.
Molly
Poecilia sphenops
A livebearer that actually grazes algae.
Picks green film off glass and décor more than guppies do.
Swordtail
Xiphophorus hellerii
A bigger livebearer that uses the full water column.
Active swimmer in a 20 long.
Cherry Barb
Puntius titteya
A peaceful barb for a planted 20.
Schooling color without tiger-barb nipping — if you keep six-plus.
Tiger Barb
Puntigrus tetrazona
Active school that nips unless the school is large.
Lots of motion in a 29-plus.
Angelfish
Pterophyllum scalare
A tall cichlid people treat like a tetra.
A real centrepiece in a 29 with height.
German Blue Ram
Mikrogeophagus ramirezi
A small South American cichlid for a warm sand bed.
Personality in a 20+ planted tank without oscar drama.
Electric Yellow Cichlid
Labidochromis caeruleus
Mbuna. Rock-picking African cichlid.
Grazes aufwuchs on rock in a Malawi setup.
Jack Dempsey
Rocio octofasciata
Large Central American cichlid. A pet, not a mix-in.
One adult is the show. They know the glass is a wall.
Oscar
Astronotus ocellatus
A large cichlid that acts like a dog.
Interactive. That is the whole point.
Convict Cichlid
Amatitlania nigrofasciata
Tough, cheap, and mean once they spawn.
Hardy cichlid for a species tank.
Discus
Symphysodon spp.
Show fish with show requirements.
A planted discus tank is the look people steal for photos.
Corydoras Catfish
Corydoras spp.
The correct bottom crew for a community.
Sift sand so leftover food and mulm do not sit and rot.
Bristlenose Pleco
Ancistrus spp.
The pleco that actually fits in a home tank — and eats algae.
Rasp green algae and biofilm off glass, wood, and hardscape.
Common Pleco
Hypostomus plecostomus
Sold as an algae eater. Becomes an 18-inch waste factory.
Juveniles do eat algae.
Kuhli Loach
Pangio kuhlii
Nocturnal sand noodles. They work leftover food after lights-out.
Pick food that hit the sand overnight.
Otocinclus
Otocinclus spp.
Tiny algae grazer for a mature planted tank.
Best small fish for soft green algae on leaves and glass.
Clown Loach
Chromobotia macracanthus
Snail-eater that outgrows the tank it was sold for.
Will hunt pest bladder snails.
Rainbow Shark
Epalzeorhynchos frenatum
One shark per tank. Owns the lower third.
Picks some algae and leftover food on the bottom.
Betta
Betta splendens
A single centrepiece for a heated, filtered 5–10 gallon.
The whole show in a small planted tank.
Dwarf Gourami
Trichogaster lalius
Shy top-dweller for a planted 10–20.
Uses the top third without the betta lottery.
Pearl Gourami
Trichopodus leerii
A larger, calmer gourami centrepiece.
Will pick at hydra and some leftover food at the surface.
Honey Gourami
Trichogaster chuna
Small peaceful labyrinth fish for a planted 10.
Less drama than a betta, less speed than danios.
Cherry Shrimp
Neocaridina davidi
Biofilm and leftover-food crew that also breeds.
Pick uneaten flakes and film off plants and hardscape.
Amano Shrimp
Caridina multidentata
The algae shrimp that stays aquarium-sized.
Best invertebrate for green algae on glass and plants.
Nerite Snail
Neritina natalensis
Glass-algae snail that will not flood a freshwater tank with babies.
Best snail for green algae on glass and hardscape.
Mystery Snail
Pomacea bridgesii
Hungry scavenger. Cleans leftover food; will eat plants if underfed.
Pick up uneaten food before it becomes ammonia.
Common Goldfish
Carassius auratus
Cold-water fish. Waste is the main output.
Hardy in cool, filtered volume.
Fancy Goldfish
Carassius auratus
Slower goldfish, still a waste factory.
Pet fish for a cool, filtered 20-plus — one fish, not a school.
Koi
Cyprinus rubrofuscus
Pond animal.
None in a glass box.