Open brain coral (Trachyphyllia geoffroyi) care guide

Group
Corals
Other names
Trachyphyllia, Folded brain coral, Trachy
Family
Merulinidae
Origin
Indo-Pacific, including Indonesia, Australia and Tonga; free-living on soft sand and mud in sheltered water
Water
saltwater
Temperature
22–26°C
pH
8.1–8.4
Hardness
dKH 8–12
Care level
beginner
Reef safe
yes
Lighting
Moderate
Flow
Low to medium

Care

A free-living large-polyp stony coral with a fleshy, folded or figure-of-eight shaped body. Colours include red, green, pink and tan, and it fluoresces strongly under actinic light. Naming: LiveAquaria lists it in Trachyphylliidae; current classifications place it in Merulinidae. Placement: bottom of the tank, resting on the sand rather than wedged in rockwork. Light and flow: moderate light and moderate flow. Water: LiveAquaria rates it easy. Keep calcium around 400–450 ppm, alkalinity at dKH 8–12 and magnesium around 1250–1350 ppm, and keep them steady; regular dosing of calcium, alkalinity and trace elements (or a calcium reactor in a busy reef) is needed as the coral grows. Growth: slow. Selling: this is a CITES Appendix II coral. Frags grown in the UK can be sold freely; wild-collected or imported pieces must have been legally imported with CITES paperwork. Sources: LiveAquaria (liveaquaria.com/products/brain-coral-trachyphyllia). Checked October 2026.

Diet

Photosynthetic (zooxanthellae). LiveAquaria says it does not need extra food, but it readily takes micro-plankton or small meaty foods, which help growth.

Breeding

Rarely fragged; it is usually kept as a single specimen.

Compatibility and tank mates

Semi-aggressive: it can sting corals it touches, so give it ample space on the sand bed.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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