Polli Cichlid (Haplochromis polli)

Meet the Polli Cichlid, a mouthbrooder from the Congo River

The Polli Cichlid (Haplochromis polli, long sold as Ctenochromis polli) is a small haplochromine cichlid from the lower and middle Congo River. It was described from Stanley Pool, now Pool Malebo, the lake-like widening of the river between Kinshasa and Brazzaville. Seriously Fish records it as far south as Pioka and Maninga in the lower Congo and as far north as Kwamouth. It is a river fish, not a Lake Tanganyika cichlid, and it needs to be kept as one.

Adults are not brightly coloured overall, but mature males are striking up close. Aquarium Glaser describes a blood-red throat, bright blue lips and a hump on the head, and Seriously Fish notes that the reddish-orange marking under the head intensifies when a male displays or courts. Females are smaller and plainer. Glaser also reports that these Congo cichlids are common in the wild but rarely exported.

Check the names on the label

In 2022 a revision by Genner and colleagues restricted Ctenochromis to two species from the Pangani River in Tanzania and moved the Tanganyika species C. horei to the new genus Shuja, sold by us as the Red-Spotted Spothead Hap. The reference works now list the Congo fish as Haplochromis polli, its original name. Do not confuse it with the Polli Tropheus, a Tanganyika algae-grazer.

Set it up as a river fish, not a Tanganyika cichlid

Some shops file this species with Lake Tanganyika cichlids. Following that would give it the wrong water and the wrong neighbours. OATA's care sheet for African lake cichlids gives pH 8.0–8.6 and a general hardness of 12–18°dH, while Seriously Fish gives pH 6.0–7.5 and 5–15 dGH for the Polli Cichlid.

Compare the two setups

Know exactly what you receive

One purchase supplies one live Polli Cichlid. The size option is "Standard": the fish is sent at the size currently available, which is smaller than the adult. Sex is not chosen or guaranteed, and young fish show little of the male's red throat and blue lips. The photographs show the type of fish, not the individual you will receive; barring and colour change with mood, age and lighting.

Plan one male with several females

• Group structure: Seriously Fish advises one male in all but the largest tanks, kept with several females to spread his attention.
• Female hierarchy: the females sort out their own order, so give them enough refuges to escape each other as well as the male.
• How many to buy: start with four or five young fish if you can, and rehome surplus males as they show themselves.

Check our delivery and Live Arrival Guarantee information before ordering, and browse more rare and collector fish.

Size the aquarium for an 8–11 cm cichlid

Published sizes vary. Aquarium Glaser described it as a dwarf cichlid of about 8 cm in 2015, FishBase gives 9.1 cm total length, and an earlier Aquarium Glaser note from 2007 gives a maximum of 11 cm. Adult males grow larger than females. Some shop descriptions quote 12–15 cm, which we have not found in any published source.

Seriously Fish recommends a base of at least 90 × 30 cm for a single pair. Aquarium Glaser advises against tanks smaller than 100 cm because males chase females and subordinate males. We suggest a tank of 100 cm or longer for one male with several females.

Run a three-step space check

1. Measure the base: 100 cm or more for a male and a group of females; 90 × 30 cm at the very least for a single pair.
2. Calculate the volume: our tank volume calculator turns your dimensions into litres for choosing equipment.
3. Count the refuges: at least one cave, pot or root tangle per female, spread across the tank.

Recreate a Congo river margin

FishBase describes the species as very common in its range, preferring shallow, slow-flowing water near the river banks. Seriously Fish calls it mostly a bottom-living fish and not very gregarious. The aquarium should therefore be built around a soft floor with plenty of cover.

Seriously Fish recommends a soft, sandy substrate, driftwood roots and branches, and clay flowerpots, plastic pipe or halved coconut shells to give subordinate fish places to escape the dominant male. Lighting should be fairly dim, with floating plants to diffuse it. Suitable plants include Anubias, Microsorum (Java fern), Taxiphyllum (Java moss) and potted Cryptocoryne. Aquarium Glaser likewise recommends a well-structured tank with roots, stones and large plants.

Divide the tank by function

Match warm, soft to medium water

Seriously Fish gives 24–28.3°C, pH 6.0–7.5 and 5–15 dGH, and rates the species moderate to keep because it needs a well-established tank and stable water. FishBase gives 24–26°C and Aquarium Glaser 25–28°C. The targets below sit inside all three sources.

Work with UK tap water

Medium-hard tap water, common across much of the UK, falls in this range once treated with a conditioner. Very hard, alkaline supplies may need mixing with reverse-osmosis water to bring the pH under 7.5. Compare your readings with our water matcher, and see our water chemistry guide for what each reading means.

Filter gently and keep the water stable

Seriously Fish recommends gentle filtration with some surface agitation. Choose a filter rated for the tank, direct the outlet along the surface so it ripples without creating a strong current, and keep the water stable rather than chasing exact numbers. Add new fish slowly: our aquarium nitrogen cycle guide explains why a mature filter matters.

Follow a weekly routine

1. Test ammonia, nitrite, nitrate, pH and hardness at least once a week, as OATA advises for dwarf cichlids.
2. Change about 25% of the water with conditioned water matched for temperature.
3. Siphon the open sand, leaving occupied caves undisturbed.
4. Rinse filter media in removed tank water, never under the tap.

Feed a varied, measured diet

FishBase records that wild fish probably feed on detritus, algae and small insects or crustaceans. Aquarium Glaser notes that new fish prefer live and frozen food but accept flake and granules once settled. OATA advises feeding dwarf cichlids once a day, only as much as they eat within a few minutes.

Build one measured meal

• First days: frozen brine shrimp, daphnia or bloodworm to get the fish feeding.
• Staple: a small sinking granule or cichlid pellet with some vegetable content, introduced once it eats well.
• Variety: frozen foods two or three times a week alongside the dry staple.
• Portion: what is gone within a few minutes; remove leftovers from the sand.

Settle it in during the first week

Add the fish to a mature aquarium with ammonia and nitrite at zero. OATA's floating-bag method is to switch off the lights, float the sealed bag for 10 minutes, add small amounts of tank water over up to 20 minutes, then release the fish with as little bag water as possible. Our guide on how to acclimatise new fish covers each step.

Use first-week checkpoints

Choose tank mates and manage the male

Seriously Fish says the Polli Cichlid can live in a community if tank mates are chosen carefully, and names peaceful open-water characins and cyprinids as ideal. Other cichlids are best avoided unless the tank is very large, and then only robust species. Aquarium Glaser describes males as quite aggressive towards females and subordinate males, so plenty of hiding places are essential.

Screen each companion

If you enjoy Congo River cichlids, the Lionhead Cichlid and the Blue Kongo Cichlid come from the same river system; keep them in their own aquarium or a very large shared one. Check any mix with our tank mates tool, read our cichlid care guide, and browse all African cichlids or our African dwarf and river cichlids.

Watch these health signs

OATA describes a healthy fish as having clear, bright eyes, undamaged fins, intact scales, no ulcers or bumps, normal swimming and steady breathing. Clamped fins, flicking against decor and shimmying are warning signs, as are changes in colour, breathing, appetite or hiding. In a harem, check the females daily for torn fins.

Pair each sign with an action

Breed a maternal mouthbrooder

FishBase describes the species as a maternal mouthbrooder, with the female caring for the brood. Aquarium Glaser calls the females delayed mouthbrooders, a term used for cichlids that lay their eggs on a surface and take the eggs or young into the mouth later, rather than straight after spawning. Glaser adds that the fry are not difficult to raise on newly hatched brine shrimp and small flake. Brood size and incubation time are not recorded in the sources we checked.

Help a holding female

• Watch for a female that stops eating and has a visibly full throat.
• Keep her in the main tank if she has enough cover, or move her gently to a quiet tank of the same water.
• Net her as little as possible and move her in a container of tank water rather than lifting her into the air.
• Once the fry are free, feed them newly hatched brine shrimp and fine flake several times a day.

Answer Polli Cichlid buying questions

Is the Polli Cichlid from Lake Tanganyika?

No. It lives in the lower and middle Congo River, including Pool Malebo (the old Stanley Pool) between Kinshasa and Brazzaville. It is sometimes filed with Tanganyika cichlids, but it needs softer, less alkaline water and different tank mates.

Is it Ctenochromis polli or Haplochromis polli?

Both names refer to the same fish. It was described as Haplochromis polli in 1964 and later moved to Ctenochromis. After a 2022 revision restricted Ctenochromis to two Tanzanian species, Eschmeyer's Catalog of Fishes, FishBase and Seriously Fish returned it to Haplochromis.

Is it the same as the Polli Tropheus?

No. The Polli Tropheus is Tropheus annectens, a Lake Tanganyika algae-grazer. This fish is a Congo River haplochromine with very different needs.

How big does it get?

Published sizes vary: Aquarium Glaser gave about 8 cm in 2015 and up to 11 cm in 2007, and FishBase gives 9.1 cm total length. Males grow larger than females.

What size tank does it need?

Seriously Fish suggests a base of at least 90 × 30 cm for a single pair, and Aquarium Glaser advises against tanks smaller than 100 cm. We suggest 100 cm or more for one male with several females.

What water does it need?

Seriously Fish gives 24–28.3°C, pH 6.0–7.5 and 5–15 dGH. FishBase gives 24–26°C and Aquarium Glaser 25–28°C. We suggest 25–26°C, pH 6.5–7.5 and 5–15 dGH.

Can I keep two males?

Only in a very large aquarium. Seriously Fish advises one male in all but the largest tanks, with several females so that his attention is spread, and Aquarium Glaser describes males as quite aggressive.

How does it breed?

It is a maternal mouthbrooder: the female carries the brood in her mouth. Aquarium Glaser describes females as delayed mouthbrooders and says the fry are easy to raise on brine shrimp nauplii and fine flake.

How many fish come with one purchase?

One live fish of the standard size currently available. Sex is not chosen or guaranteed.

Consult the care references

• Seriously Fish: Haplochromis (Ctenochromis) polli — current name Haplochromis polli, range, tank base, water range, decor, social structure and sexing.
• FishBase: Haplochromis polli — maximum length, temperature, Congo range, river-margin habitat, wild diet, mouthbrooding and IUCN status.
• Aquarium Glaser: Ctenochromis polli (2007) — maximum length, tank length, temperature, male aggression, feeding and delayed mouthbrooding.
• Aquarium Glaser: Ctenochromis polli (= Haplochromis polli) (2015) — adult size and male colours: red throat, blue lips and head hump.
• Genner et al. 2022, European Journal of Taxonomy 819: revision of Ctenochromis — the 2022 revision that restricted Ctenochromis to two Tanzanian species.
• OATA: How to look after dwarf cichlids — UK guidance on water quality, tank volume, acclimatisation, feeding and breeding for dwarf cichlids.
• OATA: How to look after African lake cichlids — the hard, alkaline water values used for Lake Malawi and Tanganyika cichlids, for comparison.
• Tropical Fish Co delivery policy — current dispatch days and Live Arrival Guarantee terms.