Peruvian festivum
Mesonauta mirificus
Also known as Mirificus flag cichlid
Care at a glance
- Temperature
- 75–82°F (24–28°C)
- pH
- 5.5–7.2
- Adult size
- 4.7 in (12 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
- Ucayali and upper Amazon, Peru
- Family
- Cichlidae
Overview
This is a peaceful, somewhat shy flag cichlid that pairs off rather than shoaling, so keep a single fish or a bonded pair rather than forcing a crowd. It favors the upper half of the tank, hanging at an angle among tall plants and floating cover, and it can be nervous, so it does best with calm tankmates and away from boisterous fish or fin-nippers. It is an omnivore that grazes soft plants and takes flake, pellet, and frozen foods, so feed a varied diet with some vegetable content. A pair wants around 250 liters with tall stem plants, driftwood, and shade at the surface.
In the wild
It lives in the Ucayali and upper Amazon of Peru, among floating meadows and overhanging vegetation along slow, soft, tea-tinted water. Recreate that with soft, slightly acidic water, driftwood, tall plants, and floating plants to diffuse the light. Keep the temperature around 24 to 28 C and the pH on the soft side, roughly 5.5 to 7.2, with gentle flow and cover it can retreat into when startled.
Good to know
Mesonauta mirificus is a cichlid of the family Cichlidae, reaching about 12 centimeters, and most of the flag cichlids that arrive in shipments from Peru belong to this species. The pair spawns on a leaf or firm surface and guards the young together, and breeding is of moderate difficulty. Its species name, mirificus, means wonderful or astonishing.
Did you know
Its name is a quiet compliment from taxonomy: mirificus means astonishing, an unusual flourish for a describer working to separate several nearly identical flag cichlids from one another.
Common questions
What size tank does a Peruvian festivum need?
A Peruvian festivum needs at least 66 gal (250 L). It spends most of its time in the middle.
What temperature and pH do Peruvian festivum need?
Peruvian festivum are comfortable at 75–82°F (24–28°C) with a pH of 5.5–7.2.
How big do Peruvian festivum get?
An adult Peruvian festivum reaches about 4.7 in (12 cm).
Where to buy
Some links may not be the exact species or variety.
…or ask your local fish store.
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Related species

Colombian festivum
Mesonauta egregiusFreshwater4.7 in (12 cm)66 gal (250 L)75–82°F (24–28°C)Acora festivum
Mesonauta acoraFreshwater4.7 in (12 cm)66 gal (250 L)75–82°F (24–28°C)Guyana festivum
Mesonauta guyanaeFreshwater4.3 in (11 cm)66 gal (250 L)75–82°F (24–28°C)
Flag cichlid
Mesonauta festivusFreshwater5.9 in (15 cm)37 gal (140 L)75–82°F (24–28°C)
Banded acara
Bujurquina vittataFreshwater4.7 in (12 cm)34 gal (130 L)68–82°F (20–28°C)
Blockhead Cichlid
Steatocranus casuariusFreshwater4.7 in (12 cm)25 gal (95 L)75–82°F (24–28°C)