Fish That Start With S - Page 3 of 4
Browse all aquarium fish species with common names beginning with "S". Each profile includes care requirements, water parameters, tank size recommendations, and compatibility information for freshwater, marine, and brackish species.
Smooth bandfish
Owstonia psilos
Owstonia psilos is a deepwater bandfish from off northwestern Australia - long, ribbon-bodied, reddish, and it has that neat black blotch up front on the dorsal fin. Its home turf is way down around 360-446 m, so its "cool factor" is real, but its natural lifestyle is totally a deep-reef, low-light thing rather than a normal home-aquarium fish.
Snub-nose snake eel
Kertomichthys blastorhinos
This is a weird little deepwater snake eel with a short, club-shaped snout and a burrowing, bottom-hugging lifestyle. It is basically a science-only fish - it's known from a single specimen collected off French Guiana, so there is no real aquarium trade care info to lean on.
Southern Smiler
Opistognathus jacksoniensis
This is an Aussie jawfish that lives in sandy-rubble areas near reefs and basically runs a little burrow like its own front porch. When its feeling safe, it will hover right at the entrance and dart back tail-first if anything spooks it. Super cool fish, but it is absolutely the type that needs the right setup (deep substrate and a tight lid) to do well.
Southern banded guitarfish
Zapteryx xyster
This is a little guitarfish from the tropical eastern Pacific that cruises sandy and rocky bottoms and comes out more at night to hunt. The coolest thing on adults is the yellow ocelli (eyespots) sitting in the dark bands across the back - it looks like someone dotted it with paint. It is a true saltwater ray-like elasmobranch, so think big footprint, lots of sand, and a heavy meaty diet.
Southern blue catfish
Ictalurus meridionalis
This is basically the tropical cousin in the blue catfish group - a big, bottom-hugging (demersal) river catfish from the Usumacinta region. It gets way too large for normal aquariums, but if you ever see one in person the wide head, whiskers, and bulldozer vibe make it pretty unforgettable.
Southern lightfish
Ichthyococcus australis
This is a deep-ocean little lightfish that lives way down in the dark and uses photophores (tiny light organs) for camouflage and signaling. It is a pelagic marine species from the southern hemisphere, and its whole vibe is "midwater stealth" rather than anything you would ever keep like a normal aquarium fish.
Southern mountain swordtail
Xiphophorus monticolus
Xiphophorus monticolus is a small, wild-type swordtail from Mexico that tends to hang in deeper pools in fast headwater streams with rocks and riffles. Males show a slender sword with darker edging and faint orange striping that can fade as they age, so its charm is more subtle than the gaudy domestic swordtail strains. Its big "gotcha" is that it is not a generic warm, hard-water livebearer - it comes from cooler, cleaner, flowing habitats, so it appreciates lots of oxygen and good maintenance.
Southern platyfish
Xiphophorus maculatus
This is the classic platy-the little livebearer that's been bred into a ridiculous number of colors, but the wild-type is more of an olive-brown fish with dark blotches. They're super active, always cruising for snacks, and you'll see fun social behavior when you keep them in a small group. Also: if you mix males and females, you'll almost certainly end up with fry-these guys don't waste any time.
Southwell's pipefish
Siokunichthys southwelli
A tiny tropical marine pipefish from Sri Lanka and the Philippines. Like many syngnathids, it is a slow, deliberate feeder that may require abundant small live foods and low-competition tankmates in captivity.
Speckled butterfly loach
Beaufortia polylepis
Beaufortia polylepis is one of those little hillstream loaches that looks like a tiny freshwater stingray with a speckled pattern, and it spends its day suctioned onto rocks grazing biofilm. The big trick with them is not "special water" so much as lots of oxygen and brisk flow - think cool, clean stream vibes, not a warm, still community tank.
Spikefin goby
Discordipinna griessingeri
This is that tiny little reef goby with the crazy tall first dorsal spines and orange striping that makes it look like a living piece of candy. It spends a lot of time tucked into coral rubble and little crevices, then darts out to grab food, so giving it real hiding spots is the whole game. Also, it gets mixed up in the trade with the wrong name sometimes, so its worth double-checking the label before you buy.
Spinach pipefish
Microphis spinachioides
This is a freshwater pipefish from Papua New Guinea - basically a tiny river cousin of seahorses with that stiff, armored "stick" body and a little tube snout for picking off micro-crustaceans. The really wild part is the males brood the eggs, and the species is so rarely seen in the wild that a lot of info we normally lean on for aquarium care just straight-up is not documented.
Spindle Yunnan loach
Yunnanilus elakatis
Yunnanilus elakatis is a nemacheilid (stone loach) endemic to Yunnan, China (type locality: Yiliang County). Aquarium-specific husbandry data for this exact species is scarce in major references; when kept, it should be maintained like other small stream-associated stone loaches: high water quality, good oxygenation, and a fine, smooth substrate with cover.
Spindle croaker
Johnius elongatus
Johnius elongatus (Spindle croaker) is a marine, demersal sciaenid from inshore waters of the western Indian Ocean (west coast of India and Sri Lanka), reported to feed on benthic worms and crustaceans; it is primarily a fisheries/food fish rather than a common aquarium species.
Spiny lanternfish
Dasyscopelus spinosus
This is a little deep-ocean lanternfish that does the classic nightly commute - hanging deeper in the day, then rising toward the surface after dark to feed. Its body is studded with light organs (photophores), and the species name 'spinosus' comes from the spiny scales around the anal-fin base. Not really an aquarium fish at all, but it is a super cool example of open-ocean life.
Spotfin betta
Betta macrostoma
This is the famous "Brunei beauty" wild betta - a chunky, orange-red fish with an awesome little eyespot on the dorsal fin and a big attitude-free personality (until you put two males together). The really cool part is breeding: the male is a paternal mouthbrooder, and the pair does that weird "kiss" egg transfer behavior people geek out over.
Spothead lantern fish
Diaphus metopoclampus
This is a deep-sea lanternfish with rows of photophores (little light organs) that it uses down in the dark, and it does that classic up-at-night, down-by-day vertical migration. Super cool animal, but its whole lifestyle is built around cold, high-pressure midwater life, so its not really an aquarium fish in any normal sense.
Spotted Mandarin Dragonet (Picturesque/Psychedelic 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.
Spotted Vanmanenia (hillstream loach)
Vanmanenia maculata
This is one of those true hillstream loaches that lives in fast, clean river flow, and it is built like a little suction-cup torpedo for clinging to rocks. The patterning is the fun part - you get those pale-centered dark spots/bars that break up the body and help it vanish on stone. It does best in a "river tank" with lots of oxygen and current, where it spends the day grazing biofilm and generally minding its own business.
Spotted archerfish
Toxotes chatareus
This is the classic archerfish that'll actually "shoot" insects with a jet of water-ridiculously fun to watch once it settles in. It's a surface-hunter from mangroves and estuaries, so it likes harder, alkaline water and lots of open top-level swimming room (with a tight lid, because they jump). Give it a big, long tank and a group of similar-sized buddies, and it turns into a real centerpiece fish.
Spotted blue-eye
Pseudomugil gertrudae
This little blue-eye is one of those fish that looks "cute" at first glance, then you notice the electric-blue eyes and the males flashing those spotted fins at each other all day. They're happiest in a planted, kind of shady tank with gentle flow, where they'll cruise in a loose group and do constant mini courtship displays.
Spotted green pufferfish
Dichotomyctere nigroviridis
This is the classic green spotted puffer: bright lime-green with bold black spots and a ton of attitude packed into a football-shaped body. They're crazy interactive and will beg like a puppy, but they're also little beaked predators that need crunchy foods to keep their teeth worn down. The big "gotcha" is water: they're not a lifelong freshwater fish-brackish (and often more marine-leaning as they mature) is where they thrive.
Spotted robust triplefin
Forsterygion capito
This is a little New Zealand triplefin that hangs out in rock pools and shallow sheltered reefs, perched on rocks and scooting around to hunt tiny critters. The cool part is the breeding behavior - the male sets up and guards a nest under a rock, and they can darken up a lot in season.
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.