Siniperca roulei – Roule's / Slender Mandarinfish (~20 cm)

A slender, elongated perch from China’s mountain streams. Tawny in color with faint dark spots and markings, it features a pointed snout and a notably protruding lower jaw. Adults typically reach around 20 cm, although some reports mention up to 20 cm as the maximum  

Habitat & Behavior:
Native to well-oxygenated, clear mountain streams flowing over rocky substrates in China’s subtropical zones  . It is a carnivorous ambush predator, feeding largely on small fish, aquatic insects, and shrimp  

Tank Setup:

• Size: A moderate tank (~100 L or larger) with streamlined open space tailored to its slender shape.

• Decor: Use rocks, driftwood, and shaded areas to provide natural cover and mimic its native flow.

• Filtration: Efficient filtration for clean, clear, fast-moving water.

Water Conditions:

• Temperature: Optimal for cool to temperate water—likely around 18–22 °C (based on similar species).

• pH & Hardness: Neutral to slightly soft water with balanced stability supports health.

Diet:

• Strict carnivore—requires live or very fresh prey (feeder fish, shrimp, aquatic insects). May hesitate to accept non-live alternatives.

Behavior & Compatibility:

• Solitary and predatory; best kept alone or with much larger companions that are not prey. Avoid small or docile species.

Conservation Status:
Listed as Vulnerable in parts of China due to habitat degradation and overfishing  . Conservation-focused breeding and habitat protection are increasingly important.