Shrimp, Snails, and Crabs
Pencil Sea Urchin
Eucidaris tribuloides
Photo: Nhobgood ( talk ) Nick Hobgood · CC BY-SA 3.0 · Wikimedia Commons
Key facts
- Temperature23–27 °C
- pH8.1–8.4
- Adult size5 cm
- Difficulty★★☆☆☆
- TemperamentPeaceful
- WaterMarine
- Reef safeWith caution
Full profile
- Family
- Cidaridae
- Origin
- Tropical Atlantic
- Size
- 5 cm shell length
- Temperature
- 23 – 27°C
- pH
- 8.1 – 8.4
- Salinity
- 1.023 – 1.025
- Difficulty
- ★★☆☆☆
- Water type
- marine
- Behavior
- Pacific (may eat corals)
- Diet
- omnivore
- Reproduction
- releases gametes
- Reef Safe
- ⚠️ Use with caution
Notes: Thick, blunt spines like pencils. Nocturnal; effective against algae, but may damage corals.
