Severum: Care, Tank Setup, Breeding, and Varieties

The Severum (Heros efasciatus) is a medium-to-large South American cichlid from the Amazon basin, recognized for its disk-shaped body, expressive eyes, and a calmer temperament than most cichlids. Wild adults reach 8 to 12 inches (20 to 30 cm) and belong to the Cichlidae family, sharing lineage with discus and angelfish. That mix of size, personality, and color variety has kept the it in freshwater aquariums for decades.

This walkthrough covers everything a Severum keeper needs, from setting up the right tank and pairing compatible tank mates to identifying Green, Gold, and Red varieties and encouraging breeding behavior at home.

The Severum as a South American Cichlid Classic

Heros efasciatus lives across a wide stretch of the Amazon and its slower tributaries, where the water runs soft, slightly acidic, and shaded by overhanging vegetation. That habitat shapes nearly every behavior you see in captivity, from a preference for calm current to comfort around broad leaves and sunken wood.

Adult size lands between 8 and 12 inches for most captive stock, with well-fed specimens occasionally pushing past a foot. That scale changes everything about the hobby: filter capacity, tank footprint, feeding volume, and the species you can safely house alongside it. A juvenile looks manageable in a 40-gallon, but a full-grown adult needs room to turn around without scraping its fins.

Why This Cichlid Earned Its Reputation

The Severum carries a reputation as a relatively peaceful cichlid, and that label holds up in most community-style setups. its don’t shred fins the way many African cichlids do, and they often develop recognizable behaviors, including following you along the glass, taking food from your hand, and defending a chosen corner of the tank during breeding cycles. That personability is part of why the species has stayed in the trade even as flashier fish come and go.

Relative peace, though, isn’t the same as passive. A hungry adult will swallow any tank mate small enough to fit in its mouth, and a breeding pair will defend a wide perimeter around its spawning site. Treat the Severum as a cichlid first, a community fish second.

That territorial instinct shapes how much space a pair actually needs to claim and defend.

Tank Size, Water Parameters, and Habitat Setup

A 75-gallon tank is the realistic minimum for one adult, and most keepers do better with a 90- or 125-gallon long. Severums are active horizontal swimmers, so footprint beats height every time. A 75-gallon long (48 inches by 18 inches) gives an adult more usable space than a standard 75-gallon tall (36 inches by 18 inches), even though the volume is identical.

Target water chemistry sits between pH 6.0 and 7.5, soft to moderately hard, with temperatures between 75 and 84°F (24 to 29°C). Wild fish come from softer, more acidic conditions, but decades of captive breeding have produced stock that adapts well to neutral, slightly harder municipal water. Stability matters more than hitting an exact number, since rapid swings stress a fish this size faster than a less-than-ideal steady reading.

Substrate, Décor, and Flow

Sand or fine gravel works well on the bottom, since severums occasionally sift substrate while feeding and coarse gravel can clog gills. Add driftwood, flat stones, and broad-leaf plants like Amazon sword or Java fern to mirror their native conditions and give the fish places to claim as territory. Live plants also help manage nitrate between water changes.

Filtration needs to move a lot of water, since a fish this size produces a heavy waste load. Aim for a filter rated to turn over the tank volume at least four to six times per hour. Diffuse the output through a spray bar or a flow-spreading nozzle, because strong direct current pushes the fish into the lower half of the tank and suppresses normal behavior. Calm turnover, not stagnant water, is the goal.

Once the environment feels settled, what you feed, and who shares it with, drives the fish’s daily behavior.

“Aim for calm turnover, not stagnant water. Strong flow pushes a Severum into the lower half of the tank and suppresses normal feeding and display behavior.

Diet, Temperament, and Compatible Tank Mates

its are omnivores, and that shows up clearly in their wild diet of plant matter, insects, small crustaceans, and fallen fruit. A quality cichlid pellet or stick forms the backbone of a captive diet, supplemented with blanched vegetables (zucchini, spinach, peas), frozen or live insects (bloodworms, black soldier fly larvae, chopped earthworms), and the occasional high-protein treat like krill to boost color.

Feed adults once or twice daily, offering only what they finish in two to three minutes. Overfeeding this species shows up fast as poor water quality and fatty deposits around the face and belly, and a full-grown it can pack away a startling amount of food when given the chance.

Reading Body Language

Fin extension, lateral displays, and jaw locking all fall within normal territorial behavior, especially during feeding or breeding. Genuine aggression looks different: a fish pinning another against the glass, repeated chasing without breaks, or visible scale and fin damage on the subordinate. Watch for clamped fins, hiding, and refusal to eat as signs that a tank mate is being harassed rather than simply postured at.

Choosing tank mates works best when you match size, speed, and water-parameter overlap rather than relying on generic cichlid lists. Fish that hold their own include silver dollars, medium to large tetras (like buenos aires or Congo tetras), peaceful to semi-aggressive South American cichlids of similar size, and robust bottom dwellers like larger plecos and clown loaches. Avoid anything small enough to swallow, including neon tetras, small rasboras, and most adult-sized shrimp, since a curious bite is usually fatal for them.

Green, Gold, and Red Varieties in the Trade

Selective breeding has turned a single wild species into a handful of distinct color lines sold under separate names. Wild-type fish from the Amazon tend toward a greenish base with faint vertical banding, and decades of line-breeding have intensified or shifted that coloration in predictable directions. The three you’ll see most often are green, gold, and red-spotted its.

Care requirements stay identical across these color forms. The differences are almost entirely cosmetic, tied to pigment genetics rather than to size, behavior, or health needs.

Variety	Appearance	Notes
Green it	Olive to dark green base with vertical bands; closest to wild-type	Most common in the trade; the benchmark for adult size and behavior
Gold it	Yellow to gold body, often with reduced banding and pinkish belly	Same care as green; pattern tends to fade slightly with age
Red Spotted it	Green or gold base with red speckling across the face, gill covers, and flanks	Higher price due to selective breeding; color deepens with maturity

Red-spotted fish command a premium because the speckling intensifies with age, and breeders have worked for years to stabilize the trait. A juvenile often shows only a hint of red around the operculum, and the full pattern can take two to three years to develop. Buying a young fish on the promise of adult color is a small gamble, since individual variation is real even within the same spawn.

Sexing Severums and Triggering Breeding Behavior

Reliable sexing usually takes patience, because the differences are subtle until the fish reach 4 to 5 inches. Mature males develop longer, more pointed dorsal and anal fins, a slightly steeper forehead profile, and more pronounced patterning on the operculum (the bony plate covering the gills). Females tend to stay rounder in the body, with shorter, more rounded fins and a darker, often less-marked face.

None of these cues is reliable on a juvenile, and some individuals never develop the classic markers. Venting (examining the genital papilla) is the most accurate method, but it requires a steady hand and is usually done by experienced breeders rather than casual keepers.

Conditioning and Spawning

To trigger breeding, raise the temperature to the upper end of the range (around 82°F), feed high-protein foods three to four times a week, and provide a flat spawning surface like a slate, a wide stone, or a piece of cleaned driftwood. A bonded pair will clean the chosen site, darken in color, and begin displaying to each other within a few weeks of good conditions.

its are biparental substrate spawners, meaning both parents guard the eggs and later the free-swimming fry. The female tends the clutch while the male patrols a wider perimeter. Egg counts run into the thousands for a healthy pair, though typical first spawns are smaller. For higher fry survival, many breeders pull the slate or the fry once they become free-swimming and raise them separately, since even attentive parents will eat a portion of the brood.

Even a successful spawn marks the point where long-term upkeep decisions start to compound.

Long-Term Health, Common Mistakes, and Care Limits

Health problems in this species often show up late because the fish are large enough to mask early symptoms. Watch for clamped fins, a darkening of the base color, weight loss around the temples, and stringy white feces as early signs of stress, internal infection, or digestive trouble. By the time a it stops eating, the issue has usually been developing for weeks.

Prevention is simpler than treatment at this size. Maintain stable water parameters, feed a varied diet without overdoing the protein, and quarantine new arrivals for at least two weeks before adding them to a display tank.

Mistakes That Shorten Lifespan

The most frequent errors come down to scale. An undersized tank stunts growth and suppresses immune function, even when the fish appears to “fit.” Overstocking the same tank, even with peaceful species, pushes filtration past its limit and burns through the safety margin in water quality. A single it kept alone in a bare 55-gallon often develops lethargy and poor coloration, because the species is social and needs both space and structure to thrive.

A healthy adult can live 10 years or more in captivity, and a few well-kept fish have reached 15. That’s a multi-year commitment in filtration maintenance, water changes, and food costs, and it should shape the decision to bring one home as much as the appeal of the color forms.

When a Severum Is the Wrong Choice

If your water runs very hard and alkaline (pH above 7.8, GH above 200 ppm), a wild or wild-type it will struggle long-term even with careful acclimation. Smaller tanks under 75 gallons cannot support an adult regardless of how often water changes happen. And if you keep planted nano tanks or shrimp colonies, this species will systematically dismantle them.

For smaller setups, consider a ram cichlid (Mikrogeophagus ramirezi) or a keyhole cichlid (Cleithracara maronii), both of which top out around 3 to 4 inches and tolerate similar water. For harder water, an electric blue acara or a blue acara often adapts more easily while keeping a similar body plan and temperament.

Takeaways

A it rewards a keeper who plans for adult size from the start, not one who buys a 2-inch juvenile and figures it out later. The species is hardy, personable, and visually striking, but only when its tank, diet, and tank mates match its actual needs. Match the setup to the fish, and this cichlid becomes one of the most rewarding large South Americans in the hobby.

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