Variegated cardinalfish
Fowleria variegata
The Variegated cardinalfish features a distinctive mix of red, orange, and blue markings with elongated dorsal and anal fins.
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About the Variegated cardinalfish
A small Indo‑West Pacific cardinalfish with a mottled, peppered red‑brown body and a rounded caudal fin. It shelters by day in seagrass beds, shallow lagoons and reef rubble, emerging at night to feed on zooplankton and small crustaceans. Males produce grunt and “hoot” calls associated with interactions and courtship. Rare in the aquarium trade; provide ample shaded cover.
Also known as
Quick Facts
Size
8 cm
Temperament
Peaceful
Difficulty
Intermediate
Min Tank Size
63 gallons
Lifespan
3-5 years
Origin
Indo-West Pacific
Diet
Carnivore - zooplankton and small crustaceans; accepts frozen foods like mysis
Water Parameters
25.3-29.3°C
8.1-8.4
Need a heater for this species?
This species needs 25.3-29.3°C in a 63 gallon tank. Use our heater calculator to find the right wattage.
Calculate heater sizeCare Notes
- House a Variegated cardinalfish in at least a 63‑gallon (240 L) marine tank with plenty of shaded hideouts among rubble, macroalgae, or seagrass‑like cover; it stays tucked away by day and emerges at night.
- Hold temperature at 25.3-29.3 C and pH 8.1-8.4; keep conditions steady rather than chasing a single exact value.
- Feed small zooplanktonic foods, especially frozen mysis and other fine meaty items, and time feedings for dusk or after lights-out when it naturally comes out to pick at drifting prey.
- This is a peaceful, shy fish, so pair it with calm tankmates that will not harass it or beat it to all the food during evening feedings.
- Aquascape with overhangs, caves, and grassy or rubbly zones to mimic its seagrass-and-rubble haunts and reduce daytime stress.
- You will only see it for sale once in a while, so have a quiet, shelter-rich tank and a plan for nighttime feeding before you buy.
- Courtship and social interactions can include soft grunt and “hoot” calls; males mouthbrood after spawning. Breeding protocols for this specific species are not widely reported in the hobby.
Compatibility
Good Tankmates
- Small, peaceful gobies (watchman, clown, hector's, Eviota/Trimma) that keep to the sand or rock and will not bully a shy, nocturnal planktivore
- Firefish/dartfish (Nemateleotris spp.) and other gentle midwater hoverers that share calm water columns and do not compete aggressively for food
- Assessors and royal gramma-type basslets that prefer caves and overhangs and coexist peacefully with small, hiding fishes
- Small, non-aggressive reef-safe wrasses like possum wrasses (Wetmorella) and pink-streaked wrasses (Pseudocheilinops) that will not harass or outcompete them
- Tailspot and other small Ecsenius blennies that graze algae and generally ignore quiet, nocturnal planktivores
- Cleaner/blood shrimp (Lysmata spp.) and other larger ornamental shrimp that are too big to be viewed as prey
Avoid
- Predatory fish that can swallow small cardinals (lionfish, groupers, large hawkfish, moray eels)
- Aggressive or nippy species that harass shy fishes, such as dottybacks and larger/boisterous wrasses
- Territorial damsels and aggressive clownfish (maroon, clarkii complexes) that dominate feeding and space in smaller tanks
- Tiny ornamental shrimp and micro-crustaceans (e.g., sexy shrimp) that may be eaten after lights out
Origin and natural habitat
Variegated cardinalfish (Fowleria variegata) comes from the Indo-West Pacific. In the wild it spends daylight hours tucked into seagrass beds and coral rubble, then moves out at night to pick drifting zooplankton. The body is red-brown with a peppered pattern and rounded fins. During courtship, individuals have been documented giving soft calls.
You will only see this species for sale once in a while. Plan ahead so you can offer the right habitat and foods from day one.
Aquarium setup and water conditions
Minimum tank size is 30 US gallons. This is a marine species that appreciates lots of cover and dim or dappled areas. Build branching rockwork and include pockets of fine rubble or dense macroalgae where the fish can disappear during the day, with open water nearby for night-time foraging. Provide calm, shaded spots out of direct flow so it can rest.
- Temperature: 25.3-29.3 C
- pH: 8.1-8.4
Set a lighting schedule with a gentle ramp-down. This species is most confident at dusk and early night.
Diet and feeding
In nature it hunts zooplankton and tiny crustaceans after dark. In the aquarium it accepts meaty frozen foods, especially small items like mysis. Offer finely sized fare such as enriched brine shrimp, copepod-rich blends, and minced marine foods. Feed small portions, ideally at dusk or with the lights dimmed, so it is not outcompeted.
Target-feed near its shelter with a feeding tube or turkey baster right after lights dim. This helps shy individuals start eating reliably.
Behaviour and tankmates
Variegated cardinalfish is peaceful and small (up to 8 cm). Expect a reclusive fish by day that becomes active in low light. Choose calm, non-aggressive tankmates. Large predators and fast, boisterous feeders can intimidate it and steal its food.
- Good context: quiet community of small, peaceful marine fish
- Avoid: aggressive or much larger species that view small fish as prey
- Reduce competition at feeding time if housed with active planktivores
Common problems and how to avoid them
- Goes off food: Start with small frozen foods (mysis, enriched brine) at dusk. Keep feeding zones calm and dim.
- Constant hiding under bright lights: Provide dense cover, rubble pockets, and shaded areas. Use a light ramp or longer evening period.
- Outcompeted by faster fish: Feed after lights dim and deliver food close to its shelter.
- Parameter stress: Keep stable marine conditions within 25.3-29.3 C and pH 8.1-8.4; avoid sudden swings.
- New arrivals: Quarantine to monitor feeding response and overall health before introduction.
Because this species is small and peaceful, mixing it with pushy or predatory tankmates is the fastest way to lose it. Plan the community around its shy, crepuscular habits.
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