Chalice Coral

The best-known example of the corals sold in the hobby as "chalice" is Echinophyllia aspera. The colony spreads over rock like a crust or forms wavy plates and layers at the edges. The mouths scattered across the surface are usually a different color from the tissue, so the colony looks as if it is covered with colorful "eyes." The tissue can be brown, green or red and often has a mottled pattern.

In the trade the name "chalice" covers more than one genus: besides Echinophyllia, colonies of Oxypora, Mycedium and Echinopora are also sold under this name. Prices of the color forms vary enormously. Its trade is subject to CITES Appendix II; most of the named forms sold are aquacultured frags, so choose those.

• Named chalice forms: Collector forms sold under names such as "Watermelon," "Mummy Eye" and the like, in which the eye and tissue colors follow a particular pattern. Colonies sold under the same name may belong to different genera.
• Red-green chalice: Common forms with red-mottled tissue and green or orange eyes.

It is common in many reef environments across the Indo-Pacific; it is seen especially on lower reef slopes, in lagoons and on fringing reefs. Gathering light by opening wide plates on slopes where light diminishes explains why it colors up well under moderate light in the aquarium.

• Light: Moderate, about 75–200 PAR. Place a new colony in the lower zone and raise it slowly; the color fades after a sudden increase in light.
• Flow: Moderate and indirect. Detritus should not settle on the surface, but strong flow should not lift the tissue.
• Placement: The middle zone of the rockwork; a horizontal or slightly sloping surface for plating forms.
• Water parameters: Salinity 1.024–1.026, KH 7–10 dKH, calcium 400–450 mg/L, magnesium 1250–1350 mg/L. Sensitive to KH swings. Colors stay vivid with nitrate at 2–10 mg/L and phosphate at 0.03–0.1 mg/L.

It is photosynthetic, but at night it also catches food with tentacles that emerge from the mouths. Once or twice a week, after the lights go out, slowly release fine-grained LPS food, mysis or chopped brine shrimp over the colony. Fed colonies spread faster.

It looks calm during the day, but at night it can burn neighboring corals by putting out long stinging "sweeper" tentacles and mesenterial filaments. Leave at least 10 cm of space around it. If two chalices are placed side by side, one may kill the other at the border.

Dwarf angelfish and some butterflyfish may pick at the tissue. It lives without problems alongside most reef fish.

Thin plates at the edge are cut with coral cutters, thicker parts with a diamond-blade saw. Each piece must have at least one mouth. The cut edge heals slowly; the pieces should be watched for a few weeks under low flow and moderate light. Because growth is slow, named forms are expensive.

• Tissue recession: Too much light, KH swings or stinging from a neighboring coral are common causes.
• Color loss: Seen after a change in lighting; the colors usually return within a few weeks.
• Detritus and algae on the surface: If flow is insufficient, the tissue gets covered; adjust the flow.