Diadem acara

Aequidens diadema

Also known as Crown acara

FreshwaterFish

Diadem acara (Aequidens diadema) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 4.8–6.5
Adult size: 5.9 in (15 cm)
Minimum tank: 66 gal (250 L)
Temperament: Mostly peaceful
Social behavior: Solitary
Tankmates: Tankmates with caution
Swim level: Middle
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: Upper Negro and Orinoco blackwaters
Family: Cichlidae

Overview

This is a calm, medium-sized acara that pairs off and holds a territory, so keep it as a single fish or a bonded pair rather than a crowd. It occupies the middle and lower water, patrolling among wood and leaf litter. It is mostly peaceful but becomes protective around a spawn, so pick tankmates with some care: peaceful, soft-water community fish of medium size, kept clear of the pair's chosen corner at breeding time. Feed an omnivore diet of quality pellets, frozen bloodworm, brine shrimp and the odd bit of vegetable matter. A pair needs a tank of at least 250 liters with driftwood, dim light and open swimming room in the center.

In the wild

Aequidens diadema lives in the blackwater forest streams of the upper Rio Negro and Orinoco tributaries, tea-stained, soft and acidic water flowing over sand and drowned leaves. Recreate that with driftwood, leaf litter, a sandy floor and a gentle tannin stain from botanicals. Keep the water soft and acidic, roughly 24 to 28 C at a pH between 4.8 and 6.5, with subdued lighting to suit a forest-stream fish.

Good to know

In the family Cichlidae, this acara reaches about 15 centimeters and is named for the dark diadem, a crown-like band across the nape. Unusually for its group it is a larvophile mouthbrooder: a pair spawns on a cleaned flat stone, then takes the hatched young into their mouths to carry and shelter them. That close, shared parental care keeps breeding at a moderate level of difficulty.

Did you know

The crown that names it is not a bright badge but a dark band worn low over the forehead, closer to camouflage than ornament on a fish that lives among shadowy leaf litter.