Jack Dempsey

Rocio octofasciata

Named after a famously tough boxer. Its dark body is studded with glittering blue-green jewels.

An aggressive freshwater fish that grows to 25 cm, lives in the middle of the tank and needs 22–29 °C, pH 6.5–8.0 and an aquarium of at least 200 L.

Care at a glance

Water

Freshwater

Temperature

22–29 °C (72–84 °F)

pH

6.5–8.0

Adult size

25 cm (10 in)

Aquarium

200 L or bigger (53 US gal)

Temperament

Aggressive

Group size

Fine on its own

Swims

Middle

Diet

Carnivore

Wild home

Central America

Good to know

• Territorial. Fights other territorial fish in its zone, especially in small tanks.
• Hardy. Tolerates less-than-perfect water. Great for beginners.
• Eats invertebrates. Hunts shrimp, snails and crabs.

Tank mates

Good company: Black Ghost Knifefish.

Will eat: Amano Shrimp, Betta, Black Skirt Tetra, Bloodfin Tetra, Cardinal Tetra, Celestial Pearl Danio, Cherry Barb, Chili Rasbora, Cockatoo Dwarf Cichlid, Congo Tetra, Corydoras, Crystal Red Shrimp and 26 more.

Eaten by: Asian Arowana.

Fights with: Demasoni Cichlid, Firemouth Cichlid, Flowerhorn, Pea Puffer, Yellow Lab Cichlid.

Attacks: Angelfish, Asian Arowana, Axolotl, Bala Shark, Betta, Black Skirt Tetra, Bloodfin Tetra, Boesemani Rainbowfish, Bristlenose Pleco, Cardinal Tetra, Celestial Pearl Danio, Cherry Barb and 46 more.

Eats the newborn fry of: Angelfish, Axolotl, Boesemani Rainbowfish, Bristlenose Pleco, Comet Goldfish, Discus, Electric Blue Acara, Fancy Goldfish, Firemouth Cichlid, Flowerhorn, Frontosa, Kribensis and 8 more.

Its fry are eaten by: Angelfish, Axolotl, Bala Shark, Black Ghost Knifefish, Comet Goldfish, Electric Blue Acara, Firemouth Cichlid, Flowerhorn, Frontosa, Motoro Stingray, Ornate Bichir, Oscar and 3 more.

Grown ones eat their own newborn fry, so raise the young in another aquarium.

Colours and breeding

• Classic rare
• Electric Blue legendary

In Aquarius a grown male and female breed in a healthy tank. Their young are born about 0.6 cm long and take after one of the parents.

Now and then a rare mutation shows up: Electric Blue.

The care values are the ones Aquarius uses, based on how these animals live. Tank mates follow the game's rules: water type, temperature and pH, who can swallow whom, fin nipping, temperament and territory.