Geophagus sveni — Sveni Eartheater
Family: Cichlidae
Origin: Brazil – Rio Tocantins and Rio Araguaia basins
Size: Up to 20 cm (8 inches)
Lifespan: 8–10 years
 
Natural Habitat
Environment: Clear and slow-moving waters with sandy or silty bottoms
Water Conditions: Warm, slightly acidic to neutral waters
Temperature Range: 24–28°C (75–82°F)
 
Physical Description
Body Shape: Laterally compressed with extended dorsal and anal fins
Coloration:
Subtle golden-tan base coloration
Shimmering iridescent blue-green markings on the head and flanks
A distinct dark lateral blotch
Long filaments on trailing fin edges in mature individuals
Sexual Dimorphism: Males are generally larger, more colorful, and have longer fin extensions
 
Aquarium Care
Tank Size: Minimum 250 litres (65 gallons) for a group
Water Parameters:
pH: 6.0–7.2
Hardness: Soft to moderately hard (2–12 dGH)
Temperature: 24–28°C (75–82°F)
Substrate: Fine sand — essential for natural sifting behavior
Décor:
Driftwood, smooth stones, and hardy plants
Open areas for foraging
Filtration: Moderate to strong flow with excellent water quality
 
Diet
Type: Omnivorous
Preferred Foods:
High-quality sinking pellets and wafers
Frozen and live foods (bloodworms, brine shrimp, daphnia)
Occasional vegetable matter or algae wafers
Feeding Behavior: Constantly sifts sand through the gills in search of food particles
 
Behavior & Tank Mates
Temperament:
Peaceful for a cichlid, especially in groups
Can be territorial when breeding
Social Structure: Best kept in groups of 5 or more to reduce aggression
Compatible Tank Mates:
Other peaceful South American cichlids
Corydoras, tetras, rainbowfish, or other mid-to-upper level swimmers
Avoid aggressive or fin-nipping species
 
Breeding
Spawning Method: Substrate spawner; occasionally shows mouthbrooding tendencies
Pairing: Form monogamous pairs when breeding
Fry Care:
Both parents often guard eggs and fry
Fry can be fed with infusoria and powdered foods after hatching
 
Notes
Geophagus sveni is a peaceful, striking cichlid ideal for hobbyists with moderate experience. Their constant sand-sifting behavior adds movement and interest to the lower tank zones. Best appreciated in a well-maintained, naturalistic setup with a soft sand base.