Celebes Rainbowfish

Marosatherina ladigesi

Rainbowfish

An active, schooling fish native to the karst (limestone) streams of Sulawesi, Indonesia. Known for their striking neon blue lateral stripes and yellowish fins. They strictly require hard, alkaline water to thrive and are highly sensitive to soft, acidic conditions. A peaceful species that requires plenty of open swimming space.

At a Glance

Adult Size7 cm
Body ShapeFusiform
Growth RateModerate
TemperamentPeaceful
Water TypeBrackish Tolerant
Flow PreferenceModerate
Waste OutputLow
StockingSchool of 6+

Tank Requirements

Minimum Volume75 L
Minimum Length60 cm
FlowModerate
Water TypeBrackish Tolerant
Must-Haves in the Tank
Plants - lighly covered

Water Parameters

Temperature2228°C
pH78.5
Hardness1025 dGH

Temperament & Compatibility

Aggression LevelPeaceful
2/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least6 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Hyperactive / Fast SwimmerJumper (Lid Required)Fry Predator

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard / Unsexed

Same care requirements as the base species

Also known as: Juvenile, Standard

Male

Differs in 3 traits from base species

Also known as: Show Male, Male Celebes

Adult Size8 cm
TemperamentMostly Peaceful
Behavior Traits
Hyperactive / Fast SwimmerJumper (Lid Required)Fry PredatorLong Finned (Nipper Target)

Female

Differs in 1 trait from base species

Also known as: Female Celebes

Adult Size6 cm

Celebes Rainbowfish Care Guide Summary

The Celebes Rainbowfish, scientifically known as Marosatherina ladigesi, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 7 cm and have a fusiform body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a low level of biological waste.

To thrive, the Celebes Rainbowfish requires a brackish tolerant aquarium with a minimum volume of 75 litres and a tank length of at least 60 cm. Water temperature should be maintained between 22°C and 28°C, with a pH range of 78.5 and a general hardness of 1025 dGH. A moderate water flow is preferred.

The Celebes Rainbowfish is a rewarding species to keep, provided its core environmental needs are met. This species is available in 3 varieties: Standard / Unsexed, Male, and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Celebes Rainbowfish Habitat Setup

When setting up an aquarium for the Celebes Rainbowfish, a moderate water flow best suits their natural preferences. Because this species occupies the surface and mid-level zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include light plant coverage for partial shade. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.

Celebes Rainbowfish Compatibility Notes

Classified as peaceful, the Celebes Rainbowfish is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. When choosing tankmates, their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the surface and mid-level zones can help reduce competition and territorial overlap.

Frequently Asked Questions About Celebes Rainbowfish

How big does Celebes Rainbowfish get?+
Celebes Rainbowfish (Marosatherina ladigesi) typically reaches a maximum adult size of approximately 7 cm. They have a fusiform body shape and a moderate growth rate.
What tank size does Celebes Rainbowfish need?+
A minimum aquarium volume of 75 litres and a tank length of at least 60 cm are recommended for Celebes Rainbowfish. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Celebes Rainbowfish need?+
Celebes Rainbowfish thrives in brackish tolerant conditions with a temperature range of 22–28°C, a pH between 7 and 8.5, and a general hardness of 10–25 dGH. A moderate water flow is preferred.
Is Celebes Rainbowfish peaceful or aggressive?+
Celebes Rainbowfish is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.
How many Celebes Rainbowfish should be kept together?+
Celebes Rainbowfish is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.
Does Celebes Rainbowfish have any special tank requirements?+
Yes. Celebes Rainbowfish benefits from plants - lighly covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Does Celebes Rainbowfish need a lid on the tank?+
Yes. Celebes Rainbowfish is a known jumper, and a tight-fitting lid or cover is essential to prevent escape. Even a small gap can be enough for a determined fish to leap out.

Similar Species

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Rainbowfish
15 cm Mostly Peaceful

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