Geophagus Sveni care guide
Geophagus Sveni (Geophagus sveni) — minimum tank 300 L, temperature 25-30 °C, pH 5.5-7.5.
Compiled by Aquairi from published sources · Published · Updated
Overview
Sven's Eartheater (Geophagus sveni) is a Brazilian cichlid from the Rio Tocantins basin, formally described in 2010. The body bears five or six dark vertical bars on a metallic blue-green ground and a row of dark lateral spots. Adults reach about 20 cm.
Taxonomy
- Family: Cichlidae
- Genus: Geophagus
- Scientific name: Geophagus sveni
- Common synonyms: Sven's Eartheater
Habitat
Native to slow-moving warm sections of large rivers and floodplain lakes in the Amazon basin of Brazil and adjacent countries. The species inhabits sandy substrates near submerged wood and root cover in soft, slightly acidic water.
Tank requirements
- Minimum tank volume: 300 L (79.3 US gal)
- Adult size: 15-20 cm
- Temperature: 25-30 °C (77-86 °F)
- pH: 5.5-7.5
- GH: 2-12 °dGH
- Water flow: moderate
- Lifespan: 8-12 years
- School size: ≥5 individuals
Diet
A sand-sifting omnivore that takes small invertebrates, organic detritus and plant matter from the substrate. In aquaria a moderate-protein cichlid pellet, frozen mysis and chopped earthworm work well; the species spends much of its time scooping mouthfuls of sand.
Compatibility
Peaceful for its size and well suited to large community tanks with similarly sized fish — large tetras, Corydoras, peaceful catfish and dwarf cichlids. Maintain a small group of 5+ as the species is social. The substrate must be sand to allow natural sifting behaviour.
Breeding
A biparental delayed mouthbrooder. Eggs are deposited on a flat rock and guarded for a day or two before the parents pick them up and mouthbrood them through the wriggler and free-swimming phases.
Conservation status
IUCN Red List: not formally assessed for this regional form, but the genus is widespread in the Amazon basin and the parent populations are not considered threatened. Most aquarium-trade specimens are tank-bred or sustainably collected.
Geophagus sveni Breeding Guide
Overview
Geophagus sveni is a South American eartheater native to the Tocantins River drainage in Brazil, reaching around 225 mm (10 in) standard length. Seriously Fish lists it as one of thirteen described members of the Geophagus surinamensis species group. Members of this group are substrate-spawning, biparental mouthbrooders, so the breeding behaviour described here reflects that of the surinamensis-group assemblage to which G. sveni belongs.
Sexing
Within the surinamensis group, no reliable external differences between the sexes have been observed except during spawning, when the female's ovipositor becomes visible. Because accurate sexing is essentially impossible beforehand, the recommended approach is to start with a group of juveniles and allow pairs to form naturally.
Conditioning
Fish in the group take at least a year to reach sexual maturity. Good nutrition combined with rigorous maintenance and substantial weekly water changes acts as the primary spawning stimulus. A sandy substrate that the fish can sift is appropriate for this benthophagous eartheater.
Spawning Behavior & Trigger
Spawning begins on a substrate surface such as a flat rock or piece of driftwood, which the pair clean and defend. Courtship in the group involves fin flaring, circling, gaping and head-jerking displays. The female deposits one or more rows of eggs that the male then fertilises, the process repeating numerous times over a period of several hours.
Egg & Fry Care
After the substrate phase, the adults take the eggs or larvae into the mouth for continued incubation, with both parents typically sharing brooding duties in this group. At 25-28 °C the fry of surinamensis-group species become free-swimming at roughly 8-11 days old and readily accept powdered dry foods, Artemia nauplii and microworm. The parents shepherd the fry, drawing them back into the mouth when danger is sensed.
Common Challenges
The chief difficulties are obtaining a compatible pair from a group given the lack of external sexual differences, and the long maturation period. As with related eartheaters, stable, well-maintained water and ample space are needed for pairs to settle and brood successfully.