Mono Angel - Monodactylus argenteus

Mono Angel (Monodactylus argenteus) is a striking and uniquely shaped brackish water fish known for its silvery body with black-tipped fins and high, triangular profile. Often mistaken for a freshwater angelfish due to its body shape, the Mono Angel is active, hardy, and thrives in spacious aquariums with brackish to marine conditions.

Description:

Common Name: Mono Angel

Scientific Name: Monodactylus argenteus

Family: Monodactylidae

Size: 8–10 inches

Temperament: Peaceful but active

Difficulty: Moderate to advanced

Native Region:

Indo-Pacific: coastal waters, estuaries, and mangrove swamps

Aquarium Setup:

Tank Size: Minimum 75 gallons

Temperature: 75–82°F

pH: 7.5–8.5

Hardness: Hard

Salinity: Brackish to full marine

Decor: Open swimming space, rocks, and hardy plants or marine décor

Additional Tips:

• Tankmates: Best kept with other brackish or marine-tolerant fish of similar size

• Diet: Omnivorous – feeds on flakes, pellets, seaweed sheets, and frozen or live foods

• Behavior: Fast swimmer; keep in groups of 3 or more to reduce stress

• Care Note: Requires increasing salinity as it matures – juveniles tolerate low brackish, adults do best in higher salinity or marine setups