Ram Cichlid – Dark Knight
Mikrogeophagus ramirezi var. "Dark Knight"
- Care level
- Intermediate
- Adult size
- 4–6 cm
- Minimum tank
- 60 litres
- Temperature
- 27–31 °C
Species profile
Pearl Cichlid
Geophagus brasiliensis
Common names: Pearl Cichlid, Brazilian Eartheater
Recognized speciesCichlids
Adult size
Up to 30 cm
Typical adult length 20–30 cm.
Up to 30 cm
Countries of origin
Good fit for your tank?
Good fit for
- Mature planted aquarium setups
- Intermediate shrimp keepers
Think carefully if
- The aquarium contains shrimp-eating fish
- The tank is newly cycled
- Water conditions change frequently
A large, hardy coastal South American cichlid with pearly blue spotting and stronger aggression than most Amazonian Geophagus.
Appearance and Identification
A robust olive to brown cichlid with dense blue-green pearl spotting, red fin accents, and a dark flank blotch. Mature males may develop a forehead hump.
Despite its long-standing name, it differs behaviourally and ecologically from many Amazonian Geophagus. Provenance matters because the complex may contain regional diversity.
Males are larger, more intensely spotted, longer-finned, and may develop a nuchal hump. Females are smaller and rounder when gravid.
Tank Requirements
- Suggested filter
- About 1,800–2,250 litres an hour
- Suggested heater
- About 450–675 W for this tank
- Minimum tank volume
- 450 litres
- Minimum tank length
- 180 cm
- Minimum group size
- 1
- Recommended group size
- 2
- Activity level
- High
- Flow preference
- Moderate
- Planting preference
- Moderately planted
- Hiding places
- Yes
- Lid recommended
- Yes
- Jumping risk
- Low
Use a large tank with fine sand, strong filtration, open territory, large rocks and wood, and securely protected plants. A pair needs escape routes.
Behaviour and Tankmates
Assertive, territorial, and active, with strong substrate digging and pair defence.
Keep singly or as a proven pair in a large aquarium. Group maintenance requires exceptional space.
Breeding pairs defend a broad substrate territory and can injure tank mates.
Only with robust similarly sized fish in a large tank. Avoid small fish, shrimp, timid cichlids, and delicate plants.
Water Parameters
It tolerates cooler and more mineralised water than many Amazonian eartheaters. Seasonal temperature variation is acceptable.
Parameter caveat
Do not assume peaceful Geophagus behaviour. Mature pairs can be highly aggressive and may uproot plants.
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Manual aquarium siphon and gravel cleaner
A manual siphon for routine aquarium water changes and accessible waste removal. The seller lists a hose approximately 1.6 m long.
Control the flow and keep the intake clear of fish and delicate planting. Clean the areas appropriate for your substrate and layout rather than disturbing the entire planted bed.
Daraz NepalCheck availability on Daraz
Feeding
- Diet types
- Detritivore, Insectivore, Omnivore
- Feeding frequency
- Daily
- Preferred foods
- Quality sinking cichlid pelletUse a staple pellet appropriate to the fish size and mouth shape.
- Chopped shrimp, mussel, or earthwormOffer clean unseasoned portions as rotating protein foods.
- Blanched leafy greens or peasUseful for omnivorous and plant-eating species; remove leftovers promptly.
- Frozen krill or mysisFeed in moderation to add variety and support colour.
An omnivorous substrate feeder taking invertebrates, plant matter, detritus, and prepared foods.
Use balanced pellets and varied whole foods. Avoid rich protein-only feeding.
Breeding
- Breeding type
- Egg Layer, Substrate Spawner
- Breeding difficulty
- Moderate
- Breeding temperature
- 25 °C
- Breeding pH
- 7
- Brood or egg count
- Several hundred to more than 1,000 eggs.
- Incubation
- 3 days
- Parental care
- Biparental care
- Baby foods
- Newly hatched brine shrimpSuitable after yolk absorption for most cichlid fry.
- Crushed high-quality cichlid pelletIntroduce gradually as fry grow.
- Finely chopped frozen cyclopsUseful supplementary food for larger fry.
A biparental substrate spawner. Eggs are laid on rock, wood, or a cleaned pit and both parents defend the brood.
Habitat and Origin
- Geographic origin
- Brazil, South America, Uruguay
- Natural habitat
- Brackish Water, Freshwater River, Lake, Reservoir
- Aquarium contexts
- Freshwater Aquarium, Large Freshwater Aquarium, Species-Only Aquarium, Temperate Aquarium
- Audience level
- Intermediate
Classification
- Profile type
- Recognized species
- Genus
- Geophagus
- Family
- Cichlidae
- Species group
- Cichlids, Fish, South American Cichlids
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Red Cheek Krobia
Krobia xinguensis
- Care level
- Intermediate
- Adult size
- 10–15 cm
- Minimum tank
- 200 litres
- Temperature
- 24–29 °C
Redbreasted Acara
Laetacara dorsigera
- Care level
- Beginner
- Adult size
- 5–8 cm
- Minimum tank
- 80 litres
- Temperature
- 22–28 °C
Severum Cichlid
Heros severus
- Care level
- Advanced
- Adult size
- 16–22 cm
- Minimum tank
- 350 litres
- Temperature
- 23–29 °C