Diaphana Sun Coral Care Guide
Diaphana Sun Coral (Tubastraea diaphana) is a NON-PHOTOSYNTHETIC coral. Care covers 0-50 PAR, medium flow, reef parameters and feeding; expert level.
Compiled by Aquairi from published sources · Published · Updated
Overview
Diaphana Sun Coral (Tubastraea diaphana) is a NON-PHOTOSYNTHETIC coral in the family Dendrophylliidae. Yellow-orange Tubastraea variant. Like all Sun Corals, requires daily target feeding.
Taxonomy
- Family: Dendrophylliidae
- Genus: Tubastraea
- Scientific name: Tubastraea diaphana
- Common synonyms: Yellow Sun Coral
Habitat
In the wild, Tubastraea diaphana is reported from Indo-Pacific, where it grows in shaded, current-swept habitats such as cave walls, overhangs, ledges, and deeper or turbid zones rather than on sunlit reef flats. As an azooxanthellate (non-photosynthetic) species it carries no symbiotic algae and depends on plankton carried by the current. It forms a encrusting colony on hard substrate.
Tank requirements
- Salinity (specific gravity): 1.024-1.026
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Carbonate hardness (dKH): 8-11
- Calcium: 400-450 ppm
- Magnesium: 1280-1350 ppm
- Phosphate (max): 0.1 ppm
- Nitrate (max): 15 ppm
- Minimum system age: 6 months
Placement and lighting
- PAR (placement zone): 0-50 PAR
- Water flow: medium
Because this coral does not rely on light, place it where feeding each polyp is practical — shaded overhangs, the underside of rock, or a low, accessible ledge. Moderate, varied flow keeps detritus from settling on the polyps but should not be so strong that it blows food away before capture. Bright light offers no benefit and can encourage nuisance algae to overgrow the skeleton between polyps.
Feeding
Tubastraea diaphana is a non-photosynthetic coral: it does not host symbiotic zooxanthellae and obtains all of its energy from captured food rather than light. Each polyp must be target-fed individually with items such as mysis, reef-roids. Feeding is required several times per week — for many keepers daily — once the polyps have fully extended their tentacles, usually after lights-out or in response to food in the water. Skipping feedings leads to gradual tissue recession and loss of polyps.
Compatibility
This coral is passive toward neighbours. It extends sweeper tentacles capable of stinging adjacent corals, so leave generous spacing (10-20 cm) between colonies. Reef-safe with most fish and invertebrates.
Care notes
Difficulty level: expert. Reported skeletal growth in well-tuned reef tanks is approximately 0.1-0.3 cm/month. Propagation by fragmentation is straightforward for encrusting colonies — separate branches or polyps with a bone cutter, glue to plug, allow 1-2 weeks for healing. Maintain stable alkalinity (avoid swings above ±0.5 dKH per day) to preserve tissue health.
Propagating Tubastraea diaphana (Diaphana Sun Coral)
Overview
Tubastraea diaphana is one of the sun corals in the genus Tubastraea, large-polyp stony corals with hard, non-reef-building skeletons whose polyp colours span yellow and orange shades. Like all members of the genus it is azooxanthellate, lacking symbiotic zooxanthellae and extending long tentacles at night to catch passing zooplankton, with large polyps that can take relatively large prey.
Reproductive Mode
Tubastraea species reproduce both sexually, by releasing planula larvae, and asexually. The genus spreads by budding and by forming runners that can extend over 10 cm per year, generating new polyps next to the parent colony.
Fragging / Asexual Propagation
Propagation uses this asexual budding. As the colony grows and adds polyps, daughter polyps or colony sections are separated and remounted onto rubble or plugs; larvae that settle nearby in the wild typically do so within about a metre of the parent and can likewise be grown on.
- Let the colony bud and add polyps.
- Detach daughter polyps or a section of colony.
- Mount each piece onto rubble or a plug.
- Target-feed every piece until established.
Feeding & Conditions for Propagation
Sun corals accept foods such as frozen mysis shrimp. Feeding every other day is sufficient for survival, while daily feeding enables faster growth, which speeds the build-up of new frags. Each polyp is target-fed because the coral draws nothing from light.
Sexual Reproduction
Sexual reproduction in Tubastraea produces planula larvae that can survive up to about two weeks; it has been recorded in spring, summer and winter. As with its relatives, aquarium propagation relies on asexual division rather than larval rearing.
Common Challenges
Starvation is the central risk: a sun coral that is not target-fed consistently will decline. Sun corals are regarded as relatively easy among non-photosynthetic corals, but only where the feeding routine is kept up and the resulting nutrients are exported.