Fish Species Starting with S
Browse all aquarium fish species with scientific names beginning with "S". Each profile includes care requirements, water parameters, tank size recommendations, and compatibility information for freshwater, marine, and brackish species.
The letter 'S' features a diverse range of aquarium species, from the vibrant Blue discus (Symphysodon aequifasciatus) to the unique Pajama Cardinalfish (Sphaeramia nematoptera). This category includes both popular community fish and captivating rarities, like the Spotted Mandarin Dragonet (Synchiropus picturatus), making it an exciting section for hobbyists looking to enhance their aquariums.
12 species found
Denison barb
Sahyadria denisonii
This is that sleek "torpedo" barb with the red racing stripe and black line-built for constant cruising in the middle of the tank. They're happiest in a proper group with lots of open swim room and really clean, oxygen-rich water with some flow. Get a school going and they look like a little pack of mini river missiles.
Jewelled blenny
Salarias fasciatus
This is the classic "lawnmower" blenny - a little reef perch-fish that spends its day scooting around the rocks, scraping film algae and looking like it has tiny eyebrows. Give it a mature tank with lots of live rock to graze and it will stay busy all day, but if the tank is too clean it can slowly starve unless you supplement greens.
Spotted scat
Scatophagus argus
Spotted scats are those chunky, disc-shaped brackish fish with the peppered "polka dot" pattern that changes a lot as they grow. They cruise around in groups, eat basically anything you offer, and they're tough as nails-just don't fall into the super common trap of keeping them in straight freshwater long-term.
Reticulated hillstream loach
Sewellia lineolata
This is the little "stingray-shaped" loach that parks itself on rocks and glass like it's magnetized, then cruises around in the current like a tiny river skate. Give it cool, super-oxygenated, fast-moving water and lots of smooth stones with biofilm, and it'll spend all day grazing and doing hilarious little dominance shuffles with its own kind.
Foxface Rabbitfish
Siganus vulpinus
Siganus vulpinus is that bright yellow "fox-masked" rabbitfish you see cruising around picking at algae all day. It's generally chill with other fish, but it can get a little bossy with similar-shaped grazers-and those dorsal spines are venomous, so nets and hands need to be treated with respect.
Pajama Cardinalfish
Sphaeramia nematoptera
This little cardinalfish looks like it got dressed in a rush-polka-dot back half, bold stripes up front, and that neon-orange tail spot that really pops under reef lights. It's a super chill, "hang in the shadows" kind of fish that likes to hover around rockwork and just cruise calmly all day. If you keep a small group, they'll often tuck in together and make your tank feel instantly more alive without causing any drama.
Knight Goby
Stigmatogobius sadanundio
Knight gobies are those chunky, spotty "estuary" gobies that perch on the bottom, scoot between caves, and then suddenly dash out like little predators. They're super fun to watch because they're territorial in a goby way (lots of posturing) and they'll even breed in caves when they're happy. They do best long-term when you treat them like an estuary fish: hard, alkaline water and (often) a bit of salt.
Cobalt blue goby
Stiphodon semoni
Stiphodon semoni is one of those little river gobies that spends its whole day perched on rocks, scooting around, and grazing biofilm/aufwuchs like a tiny underwater goat. Give it clean, oxygen-rich water and a nice algae-y rockscape, and the males especially can look unreal with that blue-green sheen and bands.
Blue discus
Symphysodon aequifasciatus
This is one of the classic wild discus from the Amazon-big, round, and super "cichlid-smart," but way more chill than most cichlids. The coolest part to me is the parenting: the fry actually feed off a mucus layer from the parents' skin for a while, which is just wild to see if you ever breed them.
Spotted Mandarin Dragonet (Green Mandarin)
Synchiropus picturatus
This little dragonet is basically a living piece of reef art-chunky fins, goofy "hovering" swimming, and those crazy psychedelic spots that look painted on. The big thing with them is they're constant pickers, cruising rockwork all day hunting tiny critters, so they're happiest in a mature tank with tons of pods (or a keeper who's ready to meet them halfway on food). If you like chill fish with tons of personality that don't bother anyone, mandarin time is hard to beat.
Mandarinfish
Synchiropus splendidus
This is the classic mandarin dragonet-the little reef crawler that looks like someone hand-painted neon blue and orange squiggles onto a fish. It spends basically all day pecking at live rock for tiny pods, and at dusk you can sometimes catch the pair-spawning "rise" if you keep a bonded male/female. Absolutely reef-safe, but it's one of those fish that does amazing only when the tank is truly mature and full of microfauna.
Upside-down Catfish
Synodontis nigriventris
The upside-down catfish is a small African mochokid catfish famous for swimming and feeding belly-up, especially under cover and along the water's surface. It has a light belly (often with darker spotting), a darker back, and prominent barbels, and it is most active at dusk and night. Peaceful overall, it does best in groups with plenty of hiding places like driftwood and caves.