Should I buy it?
Severum
Heros severus
Typical trade / ID note: Heros severus / Heros efasciatus (trade overlap)
Also known as: severum cichlid, green severum, Banded cichlid
Fishori provides conservative planning guidance, not guarantees.
Based on typical aquarium care sources; trade names can be ambiguous, so details may vary between setups. Use the numbers here as planning defaults — your room, water, and routine still shape real-world outcomes.
A large semi-aggressive cichlid at 20 cm that eats plants and needs space for a pair with territory. More peaceful than most New World cichlids of its size.
Best for
South American cichlid setups 250L or more with a bonded pair and large robust companions.
Avoid if
Planted tanks (they eat plants systematically), small fish, or tanks under 200L.
Top things that go wrong
- Mouth gap vs tiny tank mates. Predation risk toward smaller tank mates. The figure that matters is the adult mouth size against the adult prey length, not the juvenile sizes in the shop.
- Shrimp & snails. Shrimp: not safe. The fish will eat adult shrimp, shrimp fry, or both, depending on the size of the shrimp.
Common mistakeSeverum in a planted tank. They eat and uproot plants methodically. Use only Java fern or anubias attached to wood.
Common trade-name warning
This fish is often sold under different names or species variants. Care guidance is based on typical aquarium examples rather than a single exact species. Many tank-bred "severums" in shops track Heros efasciatus or colour/farm lines; true Heros severus is less often the default. Verify markings and breeding style if the label matters to you.
What most shops don't tell you
- 1.Predation risk scales with gape, night feeding, and crowding. 'they grew up together' is a schedule, not a law.
- 2.Pair in 120 L with 50 neons. The neons are eventually snacks.
- 3.Fed a single protein line with no fresh veg, leading to bloat in some lines.
- 4.Vegetable and fibre in the diet; watch for redecorating, digging, and the usual large-cichlid nitrate story if underfiltered.
About this species
Severums are round-bodied South American cichlids that reach 18 to 25 cm and are popular in larger planted tanks. They take a wide pH range, but gape, bulk, and breeding aggression make tiny tetras a poor long-term dither in small volumes.
- African Cichlid200L min · same group, comparable tank size
- Convict cichlid200L min · same group, comparable tank size
- Discus200L min · same group, comparable tank size
- Firemouth Cichlid200L min · same group, comparable tank size
- Green Terror300L min · same group, comparable tank size
- Jack Dempsey200L min · same group, comparable tank size
- Keyhole cichlid200L min · same group, comparable tank size
- Oscar300L min · same group, comparable tank size
- Angelfishalso intermediate semi-aggressive, similar tank size
- Banded leporinusalso intermediate semi-aggressive, similar tank size
- Electric Blue Acaraalso intermediate semi-aggressive, similar tank size
- Firemouth Cichlidalso intermediate semi-aggressive, similar tank size
- Opaline gouramialso intermediate semi-aggressive, similar tank size
- Rainbow / red-tailed black sharkalso intermediate semi-aggressive, similar tank size
No reverse lookups on file yet.
Plan grid
Key limits are shown above; this section adds planning detail: pH band, swim level, bioload and activity, and the radar.
Swim zones
Planning trait chart
Six indices for comparing species on paper before you spend.
- Beginner ease22
- Peacefulness30
- Community fit26
- Small-tank fit83
- Hardiness54
- Energy24
Numbers are deterministic planning indices from Fishori fields — not a scientific score of your individual fish.
Common setup sketches
Conservative patterns from Fishori fields — still run the pair checker for every species you add; sketches are not a stocking guarantee.
Avoid “one of everything” baskets — Severum belongs in a plan built around territory, line-of-sight breaks, and matched water chemistry.
Tank mate intelligence
Use the "Often compatible" lists as a shortlist, not a stocking plan. Always run the pair tool and check the footprint of your actual tank first. Verify behaviour for Severum against your own reading before you buy.
Pair-level compatibility with this fish as anchor.
Read the blocking rule on each pair page before experimenting.
Do-not-stock combinations on conservative hobby rules.
Compare with
Run a real pair check: Severum + Boesemani Rainbowfish
Behaviour, temperament, and what to watch
Prose and lists come from the same record: read temperament first, then glass-level signals so you are not surprised after day three.
Severum is semi-aggressive: stable in a calm tank, pushy with weaker fish when stressed or crowded. Treats any fish small enough to fit in its mouth as food. Mouth size at adult length matters, not the prey's listed adult size. Holds territory on substrate, in caves, or at the surface film. Break the sight lines with hardscape to keep the resident off the visitor.
Stress / aggression triggers on file
- Crowding and limited territory
- Similar-looking fish in the same tank
- Spawning, for any breeding pair
Fin nipping: Not a habitual fin-nipper, but individuals can still test fins under stress or in a crowded tank.
Predation: Predation risk toward smaller tank mates. The figure that matters is the adult mouth size against the adult prey length, not the juvenile sizes in the shop.
Territory: Holds territory on substrate, in caves, or at the surface film. Break the line of sight with hardscape, and avoid placing the tank where the fish can see its own reflection.
Planted tanks: good — easy plant ideas
In the glass: typical and warning signs
- Often calm on the glass — bursts of movement around food or tank disturbance.
- Clamped fins, gasping at the surface, hiding non-stop, or refusing food after the first week.
- Rapid breathing when parameters swing — fix ammonia/nitrite first, then reassess mates.
- Chasing one individual repeatedly, torn fins on tank mates, or food theft every feed.
- Corner guarding, flaring, or body-blocking — territory is normal until it becomes relentless.
- Separate or rehome if injuries appear, one fish is pinned, or feeding becomes a daily chase.
- If water is stable but behaviour worsens, reduce stocking or remove the highest-impact species first.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Care parameters: water, food, inverts, grouping
Chemistry and group rules sit here so you are not re-reading the same line from tank mate or temperament blocks. Swim level is in the plan grid above.
Hardness
soft
Diet
omnivore
Mixed diet: a quality flake or pellet as the staple, with frozen or live foods two or three times a week.
Shrimp & snails
Shrimp: not safe. The fish will eat adult shrimp, shrimp fry, or both, depending on the size of the shrimp.
Kept singly or as a paired setup. Check the species profile before doubling up in one tank.
Breeding behaviour depends on the species. Research before you buy a mixed-sex group of this fish.
- Hold 24 to 30 °C steadily on a real thermometer, not the dial on the heater.
- Aim for pH 5.5 to 7.5 and a hardness you can re-test in two weeks. A one-time strip in the shop car park is not a water test.
- Footprint: short wide tanks and tall narrow tanks fish differently for the same volume. Match the tank shape to the swim pattern, not just the litre count.
- Tank volume meets or exceeds 250L published minimum for adults.
- Heater can hold 24–30°C without cooking cooler-water tank mates.
- No known fin-nippers paired with long-finned fish unless you accept documented risk.
- No tank mates small enough to fit the adult mouth gap for this species.
Explore and stocking hubs
Same library as the rest of Fishori: tank-mate index for this species, category peers, guides, and litre-based stocking lists where min tank on file is within the hub volume.
Plan with tools
Pair-level rules and multi-fish stocking use the same conservative engine — add this fish in the tank builder only after mates pass pair checks.
Filtration & heating
A 250L minimum tank needs a filter rated for at least 1000L/hr turnover and a heater to hold 24–30°C reliably.
Plant suggestions
Severum does well in planted tanks. Plants compatible with 24–30°C and pH 5.5–7.5:
Profile status: partially verified · Evidence tier: medium · 3 linked source(s). Fishori does not fabricate citations.
Fishori uses conservative planning rules based on these sources.
Confidence is explained in the summary at the top of this page (same tier as here), not repeated below.
How Fishori evaluates compatibility (same logic as pair and tank tools).
- Seriously Fish. Heros efasciatus (striped / gold ‘severum’ in trade, primary care proxy)
Primary: aquarium size, water chemistry, behaviour, and community context for a Heros sp. with strong hobby coverage. Most tank-bred 'severums' in shops are this species or man-made colour lines close to it; compare with a true Heros severus (below) for breeding biology and colour.
- Practical Fishkeeping. Frequently asked questions on South American cichlids
Primary: editorial Q&A on South American cichlid communities; mentions severums in mixed-tank and compatibility thinking. Still not a one-page Heros severus monograph.
- FishBase. Heros severus
Secondary: formal species account for the binomial used in this record; the trade and Singapore farm lines often do not match wild-type severus, so this is a taxonomy anchor, not a guarantee your fish is a pure H. severus.
Evidence notes
- A dedicated Seriously Fish heros-severus URL was not found; the hobby and farm trade lean heavily to Heros efasciatus and hybrids labelled 'severum'. The SF H. efasciatus profile is therefore a pragmatic aquarium proxy, with FishBase tied to the literal binomial on the card. Expect mismatches if you are chasing wild-type or mouthbrooding biology.
- Practical Fishkeeping: magazine-level planning context; not a species data sheet. FishBase contributes natural-range size and habitat context. Translate those numbers through your heater, your water report, and your tank footprint before stocking.
- All compatibility text reflects typical hobby experience and the Fishori model. Individual fish, shop stress, and the order tank mates are added in can still defy a single-paragraph label.
- Fishori profiles work from typical aquarium trade sizes and hobby care norms. Specialist site checks and literature review for this species are not yet recorded here, so the ranges on this page are planning numbers rather than guarantees.