Watermelon Chalice

The Watermelon Chalice is one of those corals that instantly turns heads. With its deep green base, bright pink to red rim, and neon eyes, this LPS (large polyp stony) coral brings serious color to any reef tank. Despite its exotic appearance, it can be surprisingly manageable with the right care and placement.

Watermelon Chalice Basics: Placement, Lighting & Flow

This coral comes from deeper reef zones where light is softer and water movement is moderate. Recreating those conditions will keep your Watermelon Chalice happy and growing.

  • Placement: Start on the lower half of the rockwork or on the sandbed, especially under strong LEDs.
  • Lighting: Low to moderate PAR (75–150) is usually ideal. Too much light can cause the colors to fade or tissue to recede.
  • Flow: Moderate, indirect flow helps keep detritus off the surface without blasting the tissue.
  • Space: Give a buffer zone from other corals; Watermelon Chalice can extend sweeper tentacles at night.

For more on balancing light and flow for LPS corals, check out our guide to LPS coral care and placement.

Water Parameters & Feeding for Vibrant Color

Stable water chemistry is the key to keeping the rich green and pink tones that make the Watermelon Chalice so popular. Aim for reef-standard parameters and avoid large swings.

  • Temperature: 76–78°F (24–26°C)
  • Salinity: 1.025–1.026 specific gravity
  • Alkalinity: 8–9.5 dKH
  • Calcium: 420–450 ppm
  • Magnesium: 1300–1400 ppm
  • Nutrients: Low but not zero; a bit of nitrate and phosphate helps coloration.

While Watermelon Chalice corals get much of their energy from light, they respond very well to supplemental feeding.

  • Target feed small meaty foods (mysis, finely chopped seafood, reef pellets) once or twice a week.
  • Feed after lights dim, when feeding tentacles are extended.
  • Turn off or reduce flow briefly so food can settle on the coral.

Tip: Watch the coral’s response. Swelling tissue and visible feeding tentacles are good signs you’re feeding the right amount.

Common Issues & Long-Term Care

With good husbandry, your Watermelon Chalice can slowly encrust rock and become a centerpiece in the tank. Keep an eye out for a few common issues:

  • Bleaching or fading: Often caused by excessive light or sudden parameter changes. Move the coral to a shadier area and stabilize water chemistry.
  • Tissue recession: Can be due to aggressive neighbors, pests, or low nutrients. Check for stinging corals nearby and inspect at night for pests.
  • Algae on the skeleton: Indicates declining tissue health. Improve flow, manually remove algae, and correct underlying water quality problems.

If you’re building a mixed reef around your Watermelon Chalice, our beginner reef stocking guide can help you choose compatible fish and invertebrates. You can also explore our overview of chalice coral care for additional varieties and long-term growth tips.

With thoughtful placement, gentle lighting, and consistent water quality, the Watermelon Chalice will reward you with intense color and a unique growth pattern that stands out in any reef aquarium.