Threadfin Geophagus

 Quick Care Facts

• Care Level: Moderate   • Temperament: Semi-Aggressive   • Maximum Size: 10"
• Minimum Tank Size: 55 gallons   • Water Conditions: 78-86° F, pH 5.5-7.5, KH 2-7
• Diet: Omnivore   • Origin: South America   • Family: Cichlidae
• Species: Geophagus   • Aquarium Type: New World Cichlid Aquarium

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Acarichthys heckelii, also known as the Threadfin Acara and more recently, the Threadfin Geophagus, is a peaceful species that is commonly found adding action and color to South American Biotope aquariums as well as some of the less aggressive Cichlid tanks.

The Threadfin is native to shallow, sandy-bottom rivers, ponds, and lakes within the Amazon River basin of South America. Like other Geophagus species, the Threadfins will continuously sift through sand and other substrate in search of food. They have a base color of tan to gray, with slight, vertical banding and gold to green, iridescent scales on their flanks.

They also have iridescent gold to green patterns on their operculum as well as a variety of blue-green, gold and red markings on their translucent fins.

The Threadfin requires an aquarium of at least 55 gallons and should be provided with a fine, sand substrate and multiple places where they can find shelter (driftwood, rock structures, or dense vegetation).

Threadfins will sift and burrow through sand and have been known to snack on some live plant species, so live plants that attach to driftwood and rocks, or potted plants are recommended. Threadfins prefer warm, soft, acidic, and clean water as well as an area of low or subdued lighting where they can sift around for snacks.

Threadfins prefer to live in groups and are relatively peaceful Cichlids that have been successful in a community environment, but are more commonly kept in species or biotope-specific aquariums (or housed with other Cichlids). Tank mates should be considered carefully and should be comparable in size.

The Threadfin is an omnivore that generally feeds from the bottom of the aquarium (but will surface for frozen bloodworms) and should be fed a variety of foods, such as live, prepared, frozen or freeze-dried: brine shrimp, bloodworms, blackworms, krill, flake food, and soft, sinking, Cichlid pellets.

Threadfins are brood caring, cave-breeders and getting them to breed may be difficult. To stimulate breeding, feed a high protein diet (live or frozen foods) and raise the water temperature to 88° F for a few days and let it drop to around 77° F for the next few days (to simulate the wet season for spawning).

The female Threadfin will lay around 500 eggs in a carefully cleaned, cave-like structure (driftwood, rock, substrate, or artificial). Threadfin parents have been known to eat the eggs when spawning in captivity and it may become necessary to move them to a separate tank (with the same water) once they are fertilized. The eggs will hatch in a few days and the fry should be free-swimming within 1-2 weeks.

The fry can be fed a diet of baby brine shrimp or crushed flake food and then be moved to other foods as they mature. The fry should be removed from the aquarium after 2-4 weeks.