Parnaíba Eartheater
Geophagus parnaibae
The 'Compact Parnaíba Sifter' (14-16 cm). The parnaibae is the miniature jewel of the large Eartheaters. It grows to barely 15 cm (6 inches) in length, retaining the protrusible lips and benthic vacuum cleaner habits of its enormous cousins. Rustic and peaceful, it lives in tireless schools that transform the sandy bottom layout every day. Perfect for community tanks from 120 cm (4 feet) and up, it readily accepts even medium-hard tap waters typical of its river of origin.
Water Temperature
25 - 30 °C
pH Value
6 - 7.5
Water type
Freshwater
Tank level
Bottom
Adult size
15 cm
Minimum tank volume
>= 180 L
Minimum group
6
GH
2 - 12 dGH
KH
1 - 6 dKH
TDS
40 - 240 ppm
Conductivity
63 - 375 uS/cm
Species description
Geographical Origin and Habitat: Endemic to the Parnaíba River basin (Northeast Brazil). In nature it frequents the classic clear water biotopes with moderate currents and immense banks of fine sand in which it sifts its food.
Taxonomy and Morphology: Parnaíba Eartheater (Geophagus parnaibae). It is the smallest of the "surinamensis" complex. It possesses the classic slender and compressed "horse head" shape, but stops at only 14-15 cm (5.5-6 inches) in size.
Social Behavior: A nano-giant cichlid, peaceful and gregarious. Must be kept in groups of at least 6 individuals; it wastes away solitary. Maintains a stable hierarchy through "lip-locking" (kisses) and bloodless lateral displays.
Coloration and Sexual Dimorphism: Silvery-olive background, but in reproduction it "explodes" in iridescent turquoise, gold and red horizontal stripes, especially on the gill operculum. Has the classic lateral black spot. Males slightly larger and with pointed filaments.
Care, breeding and tankmates
Aquarium Setup: Paradise for "only" 120 cm (48 inches) aquariums that cannot host large Geophagus. Very fine sand (10 cm / 4 inches thick), branches and dry leaves. NO sharp quartz. Dimmed lighting and gentle current.
Diet and Feeding: Tireless benthic sifter. Sinks its snout into the sand swallowing it to filter micro-prey. Offer bloodworms, washed tubifex and sinking vegetable and protein micro-pellets. Eats very slowly, do not pair with voracious fish.
Water Quality: Very sensitive, like all Geophagus, to high nitrate concentrations. Requires pristine water; the accumulation of dirt in the sand generates lethal necrosis (Hole-in-the-head disease).
Compatibility and Cohabitation: Ideal companion for large South American community tanks, together with Corydoras (which it tolerates), small loricariids and large schools of Tetras (Cardinals, Rummy Nose). DO NOT pair with aggressive cichlids.
Aquarium Breeding: Biparental larvophile mouthbrooders. The eggs (about 100) are laid on a hard surface (a flat root or a stone). After 2-3 days of fanning, at hatching, they are swallowed and brooded in the mouth by the parents for 2 weeks.
Risks and Diseases: Gill wear and starvation if housed in aquariums with coarse gravel that it cannot chew, resulting in stress, loss of color and digestive blockages.
Geographic Origin and Distribution
Endemic to the Parnaíba River basin (Northeast Brazil). In nature it frequents the classic clear water biotopes with moderate currents and immense banks of fine sand in which it sifts its food.
Origin
Tropical oceans and reefsAmazon, Orinoco, and Guianas
Fish profile
- Temperament
- Semi-aggressive
- It is a mild-mannered cichlid. Unprovoked aggression is very rare. It is a wonderful centerpiece fish.
- Diet
- Omnivore
- It is an eartheater. Feed sinking pellets and frozen bloodworms. A fine sand substrate is mandatory.
- Life expectancy
- 10 years
- This species, considered one of the smaller Geophagus, has an average life expectancy exceeding 10 years in captivity under optimal care. Keeping the water free of pollutants and providing a varied diet are the primary factors to guarantee its longevity. Being delicate in the early stages, they require constant environmental stability.
- Adult size
- 15 cm
- The catalog's scalar value is 15 cm. The FishBase SPECIES table (v25.04 snapshot) source reports a maximum adult measurement of 7.59 cm for this species, recorded as standard length (SL). The taxonomic record consulted is Geophagus parnaibae (v25.04); male or unsexed record. These figures are not interchangeable: the first is the profile's editorial reference, whereas the second is a published maximum under a specific measurement convention; differences among sources can reflect sex, population, life stage and measuring method.
- Sex ratio
- Pair
- Keep them in groups. This diffuses natural aggression. Pairs will emerge as they mature.
- Feeding frequency
- Twice daily
- It constantly sifts the sand. Feed multiple small meals daily. This mimics natural continuous foraging.
- Bioload
- This fish produces a high bioload. Robust biological filtration is essential. Frequent water changes are necessary.
- Flow
- Stagnant
- It originates from riverine environments. It prefers moderate water flow. Provide resting areas with calm water.
- Reproduction
- Oviparous
- Many are mouthbrooders. Parents fiercely guard eggs and fry. Breeding pairs form naturally over time.
- Compatibility & tankmates
- It is generally peaceful. It fits well in community tanks. It becomes territorial during spawning.
- Tank level
- Bottom
- It stays at the bottom. It continuously sifts the sand. A large footprint is required.
Scientific Parameters & Models
FishBase
Window to the official scientific data of the species
Data synced on: 06/15/2026
- Trophic level
- 2.5 ± 0.1 se
- Resilience
- High (less than 15 months)
- Phylogenetic uniqueness (PD50)
- 0.5
- Bayesian Length-Weight
- a = 0.02042, b = 3.02
- VulnerabilityLow vulnerability (10 / 100)
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
Related species
Recommendations grouped by close relatives, companion choices, and similar care.
