Red Spot Severum (Heros severum)

Choose a substantial South American cichlid

The Red Spot Severum (Heros severum) is a South American cichlid from the family Cichlidae that reaches 20 cm. It suits an intermediate keeper who can provide a large, mature aquarium, maintain stable water quality and assess cichlid behaviour carefully. Its deep-bodied form gives it the visual presence expected from a centrepiece fish, and it mainly uses the middle region of the aquarium.

Plan the complete setup around its adult length rather than the size delivered. A smaller fish still needs a route into its permanent aquarium, including enough swimming room, suitable filtration and companions chosen for their adult size and temperament. This is not a fish for a small temporary community that has no realistic upgrade plan.

One fish can form the focus of a robust community. A pair is another possible group-care pattern, but space alone does not make two cichlids compatible: their behaviour must be watched and a separation plan kept ready. Keep the aquarium lightly stocked while the biological filter adjusts to the fish’s waste output.

Browse our South American cichlid collection when comparing this fish with other cichlid choices, but assess each candidate on adult size, temperament and water needs rather than appearance alone.

Understand the animal and size you order

One purchase supplies one Red Spot Severum in the size selected. The live size selector may show the labels 3 - 4 cm, 4 - 5 cm, 5 - 6 cm, 6 - 7 cm, 7 - 9 cm, > 8 cm, 10 - 12 cm, 13 - 15 cm and 15 - 17 cm. Use the live selector to see the precise choices presented when ordering.

The size you select is the size supplied, not the adult size. Dispatch size describes the fish when it leaves us; it is not a promise that growth stops at that measurement. Build the aquarium, filtration and compatibility plan around the 20 cm adult figure even when choosing one of the smaller labels.

Sex is guaranteed only when the selected option explicitly states male or female. This Red Spot Severum listing has no sex-guaranteed option.

Some gallery images have been digitally enhanced to improve image quality. They show the listed type of animal rather than guaranteeing the exact markings of the individual supplied, so natural colour and pattern can vary.

Colour and markings can also vary in appearance with lighting, viewing angle and the fish’s condition. Choose the animal for its long-term space and care needs rather than expecting a live fish to reproduce every colour shown in an illustrative scene.

Check the decisive care numbers

Plan for an adult length of 20 cm and an aquarium of at least 300 litres. Keep the water at 24–27°C, pH 6.5–7.5 and 4–12°dH, with carbonate hardness of 3–10°dKH. The OATA American-cichlid guidance supplies these water values for the group and recommends at least 300 litres for larger species over 15 cm.

Keep ammonia and nitrite at zero. Nitrate should not rise more than 20 mg per litre above the normal tap-water level. Those readings turn a broad care plan into practical weekly decisions: if ammonia or nitrite appears, stop adding fish, test again and correct the water-quality problem before increasing feeding or stocking.

Plan the aquarium around adult growth

Use at least 300 litres as the starting aquarium size for this 20 cm cichlid. OATA applies that minimum to American cichlids over 15 cm, placing this fish on the larger side of its group-care framework. More water also changes conditions more slowly, giving the keeper more time to notice and correct changes in temperature or waste levels.

Allocate space before adding companions

• For one fish: preserve an open middle swimming area and do not fill the aquarium to its apparent capacity with companions.
• For a proposed pair: provide separate cover and keep a workable way to divide or separate the fish if territorial behaviour develops.
• For a community: calculate every resident at adult size and consider the combined waste load, not just whether the fish physically fit today.

Fine aquarium gravel or sand is appropriate group guidance because many American cichlids dig or sift the substrate while feeding or breeding. Secure decorations so digging cannot leave them unstable. Arrange wood, plants or other cover without blocking the main swimming area, and check that the fish cannot become trapped behind heavy objects.

Live plants may be dug up or eaten by American cichlids. Treat planting as part of the layout rather than an immovable feature: protect roots, use securely positioned plants, or include suitable artificial cover where repeated digging would otherwise leave the aquarium bare.

A dispatch-size fish may look small in a 300-litre aquarium, but that is preferable to making several disruptive moves as it grows. A permanent setup allows the filter, layout and social plan to develop around the same adult fish. Measure access routes, cabinet support and maintenance clearance before filling the aquarium so weekly care remains practical.

Hold water within the working range

Keep the aquarium at 24–27°C, pH 6.5–7.5 and general hardness of 4–12°dH. Carbonate hardness should remain within 3–10°dKH. Stability within these working values matters more than repeatedly adjusting the aquarium towards a chosen midpoint.

Test the values that drive action

• Temperature: use a reliable aquarium thermometer and check it during routine observation.
• Ammonia: maintain zero mg per litre.
• Nitrite: maintain zero mg per litre.
• Nitrate: keep the increase to no more than 20 mg per litre above the normal tap-water level.
• pH and hardness: compare the aquarium with the source water before making changes.

Our water chemistry guide explains what each test measures, while the water matcher helps compare measured values with the stated range. Record results with the date, water change and any unusual observation. A sequence of readings is more useful than one isolated number because it shows whether conditions are stable or moving.

If ammonia or nitrite is detectable, treat that result as urgent. Pause further stocking, check the filter for interrupted flow or blockage, remove uneaten food and perform an appropriate conditioned-water change. Continue testing until both readings return to zero. Do not try to hide a waste problem by feeding more lightly without also checking filtration and maintenance.

Avoid sudden chemistry changes made only to chase a precise number. Test tap water as well as aquarium water, use tap-water conditioner on replacement water and make gradual, measured decisions. If pH or hardness moves unexpectedly, check the source water, recent additions and maintenance history before adding chemical adjusters.

Establish filtration before the fish arrives

Run a well-established biological filter before introducing this fish. The RSPCA’s aquarium welfare guidance explains that fish release toxic ammonia and that filter bacteria convert it first to toxic nitrite and then to safer nitrate. A filter therefore needs living bacterial capacity as well as water movement.

Prepare and mature the aquarium before choosing an arrival date. Our first tropical aquarium guide sets out the preparation sequence. Confirm zero ammonia and zero nitrite with tests; clear-looking water alone does not show that the biological filter can process fish waste.

Match the filter to a large cichlid

• Maintain continuous flow through biological media.
• Position the return so the whole aquarium circulates without creating an unusable swimming area.
• Check intakes and outlets for blockages during weekly maintenance.
• Leave room for media to be rinsed gently without dismantling the aquarium.
• Increase livestock slowly so bacterial capacity can adjust as feeding and waste rise.

Overstocking or adding several fish quickly can produce new tank syndrome because the bacterial population cannot yet process the increased waste. A large aquarium reduces rapid swings, but water volume cannot replace a mature filter. Keep the first stocking plan conservative and use test results to decide when the system is stable.

Never rinse established filter media under tap water. Chlorine or chloramine may damage the bacteria on which biological filtration depends. When cleaning is needed, swish the media lightly in aquarium water removed during a partial water change, preserve as much bacterial material as possible and restore normal flow promptly.

Feed a varied cichlid diet once daily

Feed once a day, offering only what the fish can finish within a few minutes. OATA describes American cichlids as generally omnivorous, often with a preference for meaty foods. Use an appropriately sized cichlid pellet or granule as the regular prepared food and supplement it with suitable frozen or freeze-dried items.

Build variety without increasing the portion

• Choose pellet or granule size that the fish can take cleanly.
• Use daphnia, brine shrimp or bloodworm where the item size suits the fish.
• As the fish grows, suitable larger foods from OATA’s group guidance include cockles, lance fish or prawns.
• Rotate foods across different days rather than combining a full portion of every food in one meal.

The few-minute rule is a limit, not a target to keep adding food until time expires. Start with a small amount, watch it being eaten and stop when feeding interest slows or pieces reach the substrate untouched. Remove uneaten food where practical before it breaks down.

Overfeeding creates more faeces and leaves food to decay, increasing the load on the biological filter. If nitrate begins rising faster than usual, or solid waste accumulates before the weekly clean, review portion size and uneaten food before assuming the filter needs replacement. A fish that begs at the glass has not measured its nutritional requirement.

Match the food to the fish’s present dispatch size while keeping the same once-daily structure. Smaller individuals need smaller pieces, not an unrestricted number of meals. Larger individuals may manage larger items, but the portion must still disappear within a few minutes. Record appetite during the first week so a later reduction is easy to recognise.

Use a repeatable weekly maintenance routine

Change 25% of the aquarium water at least once every week. Treat replacement tap water with a conditioner that neutralises chlorine or chloramine before it enters the aquarium. Keep the replacement water close enough to the aquarium conditions to avoid a sudden temperature or chemistry shift.

Complete the weekly sequence in order

1. Observe the fish before disturbing the aquarium and note breathing, swimming, colour and appetite.
2. Test ammonia, nitrite and nitrate; check pH and hardness often enough to recognise movement.
3. Siphon solid waste from accessible areas of gravel or sand while removing 25% of the water.
4. Inspect the filter intake, outlet and flow for blockage.
5. Rinse filter media lightly in removed aquarium water only when flow or accumulated debris shows that cleaning is needed.
6. Condition the replacement water, refill carefully and confirm normal filter and heater operation.

Do not deep-clean every surface and all filter media together. The biological filter depends on established bacteria, so maintenance should remove waste while preserving that community. Clean the area that needs attention and leave functioning media undisturbed.

Use the same container markings or measured method each week. In a 300-litre aquarium, 25% is 75 litres, although the actual water volume may be lower after substrate and décor displacement. Calculate the change from the working water volume where that is known, and keep the routine consistent enough to compare test results from week to week.

Check the substrate beneath feeding areas and around wood or decorations, where waste may collect. If debris repeatedly settles in one place, adjust the cleaning route or water circulation without creating a harsh current across the fish’s main swimming area. Maintenance should solve the cause of accumulating waste as well as remove what is visible.

Follow the arrival and acclimatisation steps

Be home to receive the fish because a live-animal parcel must not be left unattended. The fish is hand-bagged in pure oxygen and placed in an insulated poly box, with a heat pack when the weather calls for one. A licensed live-animal courier carries the parcel, and tracking is sent for the confirmed delivery.

When the box is opened

1. Check the parcel and fish promptly while keeping any documentation needed under the delivery and Live Arrival Guarantee policy.
2. Float the sealed bag in the aquarium for 20–30 minutes.
3. Release the fish without pouring bag water into the aquarium.
4. Observe swimming and breathing after release without adding other livestock.

Prepare the aquarium before the parcel arrives. The heater, filter and cover should be operating, and ammonia and nitrite should both read zero. Acclimatisation cannot compensate for an immature filter or unsuitable water, so complete those checks before opening the box.

Keep the first day focused on safe transfer and observation. Do not combine arrival with a major aquascape change, filter replacement or the addition of several other fish. A quiet stocking plan makes it easier to distinguish normal settling from a water-quality problem.

During the first week, check temperature, ammonia and nitrite daily enough to catch a change quickly, particularly after feeding begins. Note whether the fish swims upright, breathes steadily and takes food. If ammonia or nitrite appears, correct the water-quality problem immediately and avoid adding further fish while the filter adjusts.

Retain the size label as an arrival measurement, not an adult prediction. Growth changes space use, food size and waste output, so review the aquarium plan as the fish develops while keeping the 20 cm adult figure as the fixed planning point.

Respond to changes before they escalate

Watch for changes in swimming, breathing, colour, temperament, body condition and feeding. OATA highlights fish hanging at the surface, sitting on the bottom, swimming erratically, hiding more than normal, changing aggression, breathing faster or slower, losing condition, or losing interest in food as signs that deserve investigation.

Use observation to choose the next action

• Changed swimming or breathing: test temperature, ammonia and nitrite immediately and check filter flow.
• Reduced appetite: remove uneaten food, compare behaviour with earlier days and review water results.
• Darker or paler colour: look for a simultaneous change in hiding, aggression, breathing or social pressure.
• White spots, fluffy growths, damaged fins, missing scales, ulcers or bumps: separate the observation from guesswork and seek guidance before choosing a treatment.
• Sudden aggression: use the planned divider or separation aquarium before injuries accumulate.

Begin with water tests because even small amounts of ammonia or nitrite can stress American cichlids. Correcting filtration or water quality is a direct response to a measured problem; adding medication without a clear reason can complicate the situation.

Keep brief notes on normal appetite, preferred swimming area and interactions. A change is easier to recognise when there is a baseline. Photographs taken for your own comparison can also show whether marks, fin damage or body condition are changing over time.

If you are concerned about a health change, test the water and contact us with the results, aquarium volume, temperature, recent additions and a clear description of the signs. Those details allow the next decision to address the aquarium as well as the fish.

Choose single, pair or community planning deliberately

Begin with one Red Spot Severum unless the aquarium has been planned for a compatible pair. OATA says most American cichlids do better singly or in pairs, but temperament varies across the group. This fish is semi-aggressive and capable of becoming territorial when breeding, so a pair needs observation and a workable separation option.

Compare the three stocking patterns

Do not treat two fish selected together as a guaranteed compatible pair. Watch whether both can feed, use cover and occupy the aquarium without relentless pursuit. Brief displays differ from one fish being repeatedly pinned into a corner, prevented from feeding or physically damaged.

Breeding-related territorial behaviour can change a previously settled social pattern. Keep a divider, separate aquarium or other realistic separation method ready before that change occurs. Décor can create visual breaks, but visual barriers are not a substitute for removing a fish that remains under pressure.

Add livestock slowly. Every new fish changes both the social structure and the biological load, so evaluate one change before making another. For a compatibility assessment, send us the aquarium dimensions, adult stock list, water values and intended group sizes.

Screen every companion by size and temperament

The supported community pattern is a robust aquarium with larger shoaling species. This is a category for screening, not a universal promise: the proposed fish must also share the 24–27°C and pH 6.5–7.5 working range, fit the aquarium at adult size and tolerate a substantial semi-aggressive cichlid.

Check each proposed companion

• Adult size: assess whether either fish could injure or swallow the other as it grows.
• Temperament: avoid assuming that every peaceful label remains accurate around a territorial cichlid.
• Swimming pattern: ensure larger shoaling fish have enough open water and a suitable group, without crowding the cichlid’s middle swimming area.
• Feeding: watch that quick shoaling fish do not take every portion and that the cichlid does not monopolise food.
• Water values: use an overlap that keeps every animal within its own stated range.
• Waste load: leave enough filter capacity for the adult community rather than the dispatch sizes.

Use particular caution with very aggressive cichlids. OATA’s guidance places more aggressive American cichlids alone or with equally aggressive cichlids, which is a specialised social plan rather than a routine community. Mixing aggression levels without sufficient space and separation routes can leave the less dominant fish unable to feed or rest.

Small fish, tiny shrimp, fin-nipping fish and delicate slow-moving animals all require cautious compatibility screening. Treat those as prompts for close screening rather than fixed universal outcomes. Fin-nipping risk depends on the animals involved, while a small animal must be assessed against the cichlid’s 20 cm adult size rather than its arrival size.

Observe after every introduction. Intervene if one animal is repeatedly chased, trapped away from food, forced to the surface or bottom, or develops fin and scale damage. Rearranging cover may interrupt a territory, but persistent aggression calls for separation rather than repeated layout changes.

Answer common Red Spot Severum questions

How big does it get?

The Red Spot Severum (Heros severum) reaches 20 cm. Plan the permanent aquarium around that adult length rather than the dispatch size.

What size aquarium does it need?

Use an aquarium of at least 300 litres. OATA’s American-cichlid group guidance sets this minimum for larger species over 15 cm, and this fish is planned at 20 cm.

How many Red Spot Severums should I keep together?

OATA says most American cichlids do better singly or in pairs. Begin with one fish unless there is enough space, separated cover and a practical separation plan for a carefully assessed pair.

Is the Red Spot Severum suitable for beginners?

It carries an intermediate store care rating because the keeper must manage a large aquarium, stable water quality and changing cichlid behaviour. It suits someone confident with cycling, testing and weekly maintenance.

What does it eat?

Feed this fish once daily with an appropriately sized cichlid pellet or granule, supplemented by suitable frozen or freeze-dried foods. OATA describes American cichlids as generally omnivorous and often preferring meaty foods; offer only what is eaten within a few minutes.

What temperature and pH does a Red Spot Severum need?

Keep it at 24–27°C and pH 6.5–7.5, with general hardness of 4–12°dH. These are OATA’s group-care values for American cichlids.

Is it aggressive or likely to nip fins?

This fish is semi-aggressive and may become territorial when breeding. Treat fin-nipping as an individual compatibility risk: provide space and cover, watch interactions and separate fish if chasing or damage persists.

Which animals can live with a Red Spot Severum?

OATA names larger shoaling species as possible companions for calmer cichlids such as severums in a robust community. Match adult size, temperament and water needs, then monitor every introduction rather than treating any species as universally compatible.

How does it arrive alive in the UK?

Before opening the parcel, film every delivery continuously from the sealed parcel onward. It is hand-bagged in pure oxygen inside an insulated poly box, with a heat pack when the weather calls for one, and carried by a licensed live-animal courier. Be home to receive it, then float the bag for 20–30 minutes before releasing the fish.

Consult the care and welfare references

• OATA, How to look after American cichlids: group guidance for water values, aquarium planning, social patterns, feeding, maintenance and health observation.
• RSPCA aquarium environment guidance: the role of biological filtration in processing ammonia and nitrite.
• Tropical Fish Co delivery and Live Arrival Guarantee policy: packing, receipt and the 20–30 minute floating procedure.