- Alkalinity: 8-12 dKH - Calcium: 350-420 ppm - pH: 8.1-8.4 - Temperature: 72-78°F - Difficulty level: Easy - Description: Green Starry Polyps (Briareum spp.) are a popular, soft-coral species. They feature vibrant green, star-shaped polyps with white or yellow centers. This coral prefers moderate lighting, gentle water flow, and stable water parameters. Green Starry Polyps are relatively low-maintenance, proliferate easily, and can form mats or colonies, making them ideal for beginners and experienced aquarists seeking a striking, dynamic display.