Threadfin Acara

Acarichthys heckelii

Threadfin Acara (Acarichthys heckelii) — Varies care, Peaceful, under Other. Minimum tank in the app: 53 US gal min; aim for 75–86°F and pH 6.5–7.5. Threadfin Acaras appeal to aquarists seeking a semi-aggressive species with intriguing behaviours and striking coloration.

Threadfin Acara (Acarichthys heckelii) in a planted freshwater aquarium
Care levelVaries
TemperamentPeaceful
Min tank size53 US gal min
pH range6.5–7.5
Temperature75–86°F
Max size7.9 in (20.0 cm)
Captive lifespan8–12 years
SchoolingNo

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

South America

  • South America

Regional colours match the stocking calculator’s origin map.

Threadfin Acara Tank Setup

Create a spacious environment with ample mid-water swimming zones and sufficient cover, such as plants and driftwood, to foster comfort and reduce aggression. Opt for soft, natural substrates and moderate lighting to mimic their preferred habitat, while ensuring good water flow to maintain water quality.

What Do Threadfin Acaras Eat?

As omnivores, Threadfin Acaras adapt well to varied diets but can be competitive feeders. Offer a mix of high-quality flakes, pellets, and occasional live or frozen foods to enhance their coloration and health.

Threadfin Acara Tank Mates

Best companions include similarly sized, semi-aggressive fish that occupy different tank levels to minimize territorial conflicts. Caution is advised with overly aggressive species or fin-nippers that may stress the Acaras. Intraspecies interactions are generally peaceful, but establishing enough territory is crucial to avoid skirmishes.

Are Threadfin Acaras Good for Beginners?

Care demand varies with setup and individual fish; use the numbers above as your baseline. Aquarists often underestimate the need for tank size and filtration, leading to poor water quality and stressed fish. neglecting to provide sufficient hiding spots can result in aggression and territorial disputes, particularly during breeding.

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