Tectus fenestratus – Algae-Grazing Top Snail

Tectus fenestratus is a robust, cone-shaped top snail highly valued in marine aquaria for its effective algae-grazing behavior and durability. Native to Indo-Pacific reefs, this species spends its time on live rock, glass, and substrate surfaces, feeding on film algae and diatoms, contributing to a clean and stable ecosystem.

Key Facts:

Scientific name: Tectus fenestratus

Common name: Fenestrate Top Snail

Origin: Indo-Pacific

Adult size: 3–5 cm

Diet: Film algae, diatoms, detritus; may accept supplemental algae wafers

Behavior: Peaceful, reef-safe, active primarily during low light

Compatibility: Safe with corals, fish, and other invertebrates

Water Parameters:

Temperature: 24–27 °C

Specific Gravity: 1.023–1.026

pH: 8.0–8.4

dKH: 7–10

This species plays an important role in maintaining biological balance by consuming nuisance algae without disturbing coral polyps or sessile invertebrates. Best kept in established reef systems with sufficient natural algal growth and stable water chemistry.