Blue Orchid Peacock Cichlid (Aulonocara kadensis)

Understand this Lake Malawi peacock

The Blue Orchid Peacock Cichlid (Aulonocara kadensis) is a haplochromine cichlid intended for a carefully planned Lake Malawi aquarium. It belongs to Aulonocara, a genus endemic to Lake Malawi in East Africa, whose members are widely called peacock cichlids, aulonocaras or peacocks. Plan for an adult length of up to 7.8 cm and an aquarium of at least 250 litres. This fish suits a keeper prepared to manage hard, alkaline water, strong biological filtration and the aggressive group dynamics associated with Malawi cichlids.

Keep the aquarium at 24–26°C, pH 8.0–8.5 and 12–18°dH. Hold these values steady: Malawi cichlids are a specialised group that require hard, alkaline water. Ammonia and nitrite must remain at zero mg per litre, while nitrate should not exceed 20 mg per litre above the normal tap-water level.

Make the key decisions before purchase

• Space: use at least 250 litres, with enough swimming room and broken sight lines for an aggressive Malawi community.
• Water: confirm that the aquarium can hold hard, alkaline conditions steadily rather than trying to alter unsuitable water after the fish arrives.
• Community: plan around other Malawi cichlids or carefully screened Synodontis species that naturally inhabit Lake Malawi.
• Filtration: mature the biological filter before adding livestock and size it for the waste produced by a busy cichlid community.

All Aulonocara species are maternal mouth brooders, but this does not change the everyday priorities: stable water, controlled feeding, sufficient space and close observation of aggression. Aulonocara is strongly sexually dichromic, so adult males and females differ clearly in colour. Choose this fish for a Malawi-focused setup rather than for a peaceful mixed community.

Choose the dispatch size and plan for one fish

One purchase supplies one animal in the size selected through the live size selector. Choose from 3 - 4 cm, 4 - 5 cm, 6 - 7 cm or XL; XL has no stated centimetre measurement. The size you select is the size supplied, not the adult size.

Sex is guaranteed only when the selected option explicitly states male or female. This Blue Orchid Peacock Cichlid listing has no sex-guaranteed option.

The gallery images are representative of this type of animal rather than photographs of the exact animal supplied, so colours can look slightly different from the live animal.

Check whether the setup fits

Dispatch size changes the measurement of the fish sent, but it does not reduce the space, water-quality or compatibility requirements of the adult. Set up for the full 7.8 cm planning length from the beginning. This prevents a temporary dispatch measurement from becoming the basis for permanent stocking.

For a wider comparison of fish intended for this water type and community style, browse the African cichlid collection. Compare every prospective addition by water chemistry, expected aggression and adult space rather than by colour alone.

Plan the aquarium around the adult size

Plan for the Blue Orchid Peacock Cichlid to grow up to 7.8 cm. That adult figure, rather than the dispatch measurement, should determine the permanent aquarium, filtration capacity and stocking plan. A fish sent at one of the smaller sizes still needs a completed adult setup before it arrives.

Use an aquarium of at least 250 litres. Choose a larger aquarium for groups or mixed Malawi setups. More water also gives greater stability in temperature and water quality, although added volume does not remove the need to manage aggression.

Size the aquarium before stocking

1. Start with 250 litres or more. Do not calculate the aquarium around a temporary dispatch grade.
2. Reserve open swimming space. Rockwork and shelters must not fill the whole footprint.
3. Allow for the full community. Count the other Malawi cichlids or screened Synodontis in the same filtration and space calculation.
4. Leave capacity for waste. Malawi communities require robust biological filtration, regular testing and disciplined feeding.

Malawi cichlids vary in size, so plan every companion around its own adult size rather than this fish’s 7.8 cm.

Check the completed layout from end to end. The fish needs room to move between territories without every route passing through a single defended area. If rocks, equipment or ornaments leave only one narrow passage, simplify the arrangement before stocking. Space is useful only when the fish can use it.

Hold stable hard, alkaline water

Keep the aquarium at 24–26°C, pH 8.0–8.5 and 12–18°dH. Hold these values steady, not just within range. Test the water that will actually enter the aquarium, including conditioned replacement water, rather than relying on an assumed local-water profile.

Measure pH and hardness before choosing buffering materials. Use coral sand or a similar substrate to buffer the water, then test to confirm the finished aquarium is within range. Use our water matcher to compare measured values with these targets instead of changing chemistry by guesswork.

Respond to a result, not an assumption

• If pH is below 8.0: establish why the aquarium is outside the intended range before adding the fish.
• If hardness is below 12°dH: prepare the aquarium and replacement water consistently so routine changes do not create repeated swings.
• If ammonia or nitrite is detectable: postpone further stocking and deal with the biological-filter problem.
• If temperature moves outside 24–26°C: stabilise it before introduction rather than expecting the fish to absorb the change.

Never chase a single reading with rapid, repeated adjustments. Confirm an unexpected result with a fresh test, compare it with the source water and inspect the aquarium routine for causes. Stability comes from repeatable preparation, adequate buffering, a mature filter and regular maintenance.

Mature the filter before stocking

Use a well-established biological filter before the fish enters the aquarium. The RSPCA explains that fish release toxic ammonia; beneficial filter bacteria convert it first to nitrite, which is also toxic, and then to the safer nitrate. A filter moving water is not enough on its own: the biological media must have a functioning bacterial population.

OATA recommends an oversized filter for crowded Malawi communities and aggressive aeration to maintain dissolved oxygen. Match the filter to the whole planned population, not just the first fish. Confirm that water reaches every intake, outlet and biological-media chamber without a blockage.

Prepare the system in sequence

1. Set up the aquarium, substrate, décor, heater, filter and aeration.
2. Mature the biological filter before livestock is added. Our first tropical tank guide explains how to prepare and mature an aquarium.
3. Test until ammonia and nitrite are both zero mg per litre.
4. Confirm 24–26°C, pH 8.0–8.5 and 12–18°dH under normal running conditions.
5. Check that the intended community remains within the aquarium’s physical and biological capacity.

A filter problem demands immediate attention because even small amounts of ammonia can stress Malawi cichlids. If fish begin hanging at the surface, breathing differently, sitting on the bottom or losing interest in food, test the water before assuming the cause is behavioural.

Do not switch off essential filtration as a routine response to strong flow. Arrange outlets and décor so the aquarium retains circulation and oxygenation while offering usable swimming routes. Watch the complete tank after feeding: food should not gather in dead spots where it can decay unnoticed.

Build a usable Malawi layout

Combine open swimming room with rockwork that breaks direct lines of sight. The aquarium should not be an empty box, but it should not become a solid wall of rocks either. Each barrier must leave safe routes around it and remain stable if fish dig beneath nearby substrate.

Use coral sand or a similar substrate that helps buffer the water. Malawi cichlids often dig and rearrange the substrate, so expect the floor to move. Keep rocks secure and avoid balancing heavy pieces on loose sand where digging could undermine them.

Divide the footprint by function

Use only the hardiest plants that grow attached to décor. Do not rely on plants alone to separate territories; use stable structure and open escape routes.

Inspect the layout from the fish’s level. If one rock group allows a dominant fish to see almost the entire aquarium, split that view with another stable barrier. If a shelter has only one entrance, where one fish can trap another, provide a second route or use a more open arrangement.

Décor can also be rearranged before adding a new Malawi group. OATA notes that this may reduce aggression as fish establish new territories. Make structural changes before release, then leave the aquarium calm enough for behaviour to be assessed without repeated disruption.

Feed small, controlled portions

Feed this omnivorous peacock cichlid a varied diet based on quality cichlid pellets or granules with suitable animal content, supported by small meaty foods. Malawi-cichlid diets vary, so feed this fish as an omnivore rather than copying another Malawi cichlid’s diet.

Offer only what the fish can eat within a few minutes, twice a day. Watch the fish take the food, then remove uneaten material before it breaks down.

Build variety without losing portion control

• Staple: use an appropriate quality cichlid pellet or granule that can be eaten cleanly.
• Meaty variety: rotate small portions of frozen foods such as mysis or brine shrimp.
• Broader variety: occasional spirulina-containing food can form part of the varied omnivorous diet, but it should not displace the main balanced cichlid food.
• Portion test: stop adding food when the few-minute feeding window is reached.

Overfeeding creates two problems at once: uneaten food adds waste, and the biological filter must process the resulting pollution. If food is reaching the substrate untouched, reduce the amount at the next feed and check whether every fish can reach an appropriate particle size.

Use feeding time as a daily observation point. A fish that suddenly hangs back, spits out food or shows reduced interest may be reacting to aggression or declining water quality. Test ammonia and nitrite and watch the interactions around the feeding area before changing foods repeatedly.

Keep feeding consistent after arrival. Do not compensate for a missed or cautious first feed by adding a large portion later. Small measured portions make appetite easier to judge and keep the aquarium cleaner.

Follow a weekly maintenance routine

Change 25% of the aquarium water at least once every week. Use a siphon to remove solid waste from the substrate where debris accumulates.

Treat replacement water with tap-water conditioner before adding it to the aquarium so chlorine or chloramine does not damage fish or filter bacteria. Prepare its temperature and chemistry consistently, then add it without creating a sudden change from 24–26°C, pH 8.0–8.5 or 12–18°dH.

Complete the same checks every week

• Test ammonia and nitrite at least once per week and keep both at zero mg/L.
• Check nitrate and keep it no more than 20 mg/L above the normal tap-water level.
• Confirm temperature, pH and hardness rather than judging water quality by appearance.
• Inspect the filter for blockages and confirm that aeration and circulation remain strong.
• Siphon waste from accessible substrate without destabilising the rockwork.

If the filter needs cleaning, do not run it under the tap. Rinse it lightly in aquarium water removed during the partial water change. This reduces the loss of beneficial bacteria caused by chlorine or chloramine.

Our water chemistry guide explains what the main readings mean. Keep a simple written log of results and maintenance dates. A sequence of readings shows gradual movement that a single result can hide, making it easier to act before ammonia, nitrite or nitrate becomes a health problem.

If a weekly test shows detectable ammonia or nitrite, stop adding fish, inspect the filter and deal with the water-quality problem. If nitrate is climbing, review portion sizes, waste removal, community load and the regularity of water changes rather than relying on one unusually large intervention.

Receive and acclimatise the fish correctly

Tropical Fish Co hand-bags live fish in pure oxygen and uses an insulated poly box, adding a heat pack when the weather calls for it. A licensed live-animal courier carries the parcel. Someone must be at the address to receive it because live fish cannot be left unattended.

Follow this arrival sequence

1. Receive the parcel in person. Have the order details ready and take possession without leaving the box unattended.
2. Start filming before the parcel is opened. Film every delivery from the sealed parcel onward, with the outer box visible.
3. Open it in one continuous take. Show the fish still inside the sealed bag so its condition can be seen before anything is disturbed.
4. Open and inspect the parcel on the day it arrives. Keep the continuous video for any Live Arrival Guarantee claim.
5. Float the bag for 20–30 minutes before releasing the fish. Acclimatise slowly and do not pour the bag water into the aquarium.

The unboxing video and order number are required for a Live Arrival Guarantee claim. Send them on the day the fish arrives so the issue can be assessed promptly. The full conditions are set out in the delivery and Live Arrival Guarantee policy.

Complete the aquarium checks before the parcel comes through the door. Temperature should already be 24–26°C, ammonia and nitrite zero mg/L, and the hard, alkaline water stable.

After release, observe swimming, breathing and interactions without adding another unplanned change. The first task is to confirm that the fish can move through the prepared layout and is not being pinned into one area by an established tank mate.

Manage introductions and the first month

Add fish only to a mature aquarium with zero ammonia and zero nitrite. Increase the total population slowly because the beneficial bacteria in the filter must grow as fish numbers and feeding increase. Adding too many fish too quickly can produce new tank syndrome, allowing toxic ammonia and nitrite to rise.

OATA also recommends adding Malawi cichlids in planned groups so one newcomer does not receive all the aggression while settling. Plan each introduction carefully, keep the aquarium within its biological capacity and avoid a long sequence of isolated additions.

Check the first week at clear decision points

• At each feed: confirm that the fish reaches food and eats within the few-minute feeding window.
• During routine observation: look for surface hanging, bottom sitting, erratic swimming, unusual hiding or a sudden change in aggression.
• At the weekly test: confirm zero ammonia, zero nitrite and acceptable nitrate before considering another addition.
• At the filter: check flow and aeration without dismantling biological media unnecessarily.

Use the first month to test the plan

Watch whether territories remain usable as the fish settle. Rearranging décor may help when a new group is introduced, but repeated changes can make behaviour harder to interpret. Make one purposeful adjustment, then assess its effect.

Healthy fish have clear, bright eyes, undamaged fins, intact scales and no ulcerations or bumps, and swim normally. Warning changes include faster or slower gill movement, darker or paler colour, white spots, fluffy growths, loss of fins or scales, changes in body condition and reduced food intake.

If any of these changes appear, test water quality first. Correct water-quality or filtration problems promptly and contact us for further guidance about the observed health change. Do not add more livestock while the cause is being assessed.

Screen every tank mate before mixing

Keep this fish only with other Malawi cichlids or with carefully selected species of Synodontis catfish that naturally inhabit Lake Malawi. Avoid unrelated community fish, including fish intended for soft, acidic water.

Every Malawi combination still needs screening because Malawi cichlids are aggressive and should be mixed with caution. Screen the complete community for shared hard, alkaline water, adequate adult space and a layout that permits fish to leave one another’s line of sight.

Use a three-part screening rule

1. Match the water: every animal must suit pH 8.0–8.5 and hard water at 12–18°dH.
2. Match the aquarium: the combined population must fit at least 250 litres with strong filtration, oxygenation and usable territory.
3. Assess aggression: avoid assuming that a shared lake or similar body shape makes a pairing safe.

Contact us for stocking advice before combining named species. Give the aquarium volume, dimensions, measured water values, present livestock and proposed additions. Compatibility depends on the whole setup rather than one fish name considered in isolation.

Manage the group rather than one pairing

Treat the Blue Orchid Peacock Cichlid as part of an aggressive Malawi community. OATA says Malawi cichlids can be kept in groups of at least 15 and slightly overcrowded to spread aggression; it also warns that small groups often fight.

Use at least 250 litres, an oversized filter and strong aeration before stocking a group. Stocking density must remain within the aquarium’s biological capacity. Zero ammonia and nitrite are non-negotiable even when a community is deliberately planned to distribute aggression.

Stage additions with purpose

• Add the more peaceful Malawi species before more aggressive species.
• Add planned Malawi introductions in groups so one individual does not receive all the attention.
• Rearrange décor before an introduction when established territories need to be broken up.
• Keep open routes around rockwork so a chased fish can move away.
• Observe every feeding to confirm that all fish can reach food.

Where sexes are known, keep more females than males of each species so males do not harass one individual female. Do not identify sex from dispatch size. Build any sex-ratio plan only around fish whose sex is known.

Intervene when behaviour changes from brief territorial interaction to persistent exclusion. Warning signs include one fish being held at the surface or bottom, hiding more than normal, losing access to food, showing damaged fins or scales, or breathing differently. Test the water as part of the response because poor water quality can occur alongside aggression.

If one fish repeatedly controls the only feeding point or passage through the aquarium, change the practical cause. Spread food within the few-minute allowance, revise the sight lines or alter the stocking plan. Do not solve persistent aggression by adding random fish: every addition increases waste and requires its own compatibility assessment.

Get clear answers before choosing this fish

How big does the Blue Orchid Peacock Cichlid get?

It grows up to 7.8 cm as an adult. Plan the permanent aquarium around that adult length rather than the dispatch measurement.

What size aquarium does Aulonocara kadensis need?

Use at least 250 litres. Choose a larger aquarium for groups or mixed Malawi setups.

How many Blue Orchid Peacock Cichlids should be kept together?

Plan a Malawi-cichlid group of at least 15, slightly overcrowded to limit aggression, because OATA warns that small groups will often fight. Use at least 250 litres and keep the population within the filter’s biological capacity.

Is Aulonocara kadensis suitable for beginners?

It suits a keeper who can maintain hard, alkaline water, zero ammonia and nitrite, strong filtration and an aggressive Malawi community. It is not a peaceful general-community choice.

What does the Blue Orchid Peacock Cichlid eat?

Feed an omnivorous diet based on quality cichlid pellets or granules with suitable animal content, plus small meaty foods. Offer only what it can eat within a few minutes, twice a day.

What temperature and pH does this fish need?

Keep it at 24–26°C, pH 8.0–8.5 and 12–18°dH, and hold those values steady.

Is it aggressive or likely to nip fins?

Treat it as an aggressive Malawi cichlid and monitor fins, scales, feeding access and hiding. Use broken sight lines, sufficient space and a screened community rather than assuming every Malawi pairing is safe.

Which animals can this fish live with?

Keep it only with screened Malawi cichlids or some screened Synodontis catfish species that naturally inhabit Lake Malawi. Avoid unrelated community fish and fish requiring soft, acidic water.

How is this fish transported to its new home in the UK?

Tropical Fish Co hand-bags it in pure oxygen, uses an insulated poly box and adds a heat pack when the weather calls for it. A licensed live-animal courier carries the parcel; receive it in person, film from the sealed parcel onward, inspect it that day and float the bag for 20–30 minutes before release.

Consult the care references

• Wikipedia: Aulonocara — genus-level range, classification, trade names and mouth-brooding biology.
• OATA: How to look after African Malawi cichlids — group water, aquarium, feeding, maintenance, behaviour and compatibility guidance.
• RSPCA aquarium environment guidance — biological filtration and nitrogen-waste management.
• Tropical Fish Co delivery and Live Arrival Guarantee policy — packing, receipt, unboxing evidence and acclimatisation procedure.