Common name
Acan corals
Scientific name
Acanthastrea and Micromussa spp.
Category
Coral
Group
Large-polyp stony corals
Environment
Marine reef aquarium
Origin
Tropical and subtropical Indo-Pacific reefs; exact range is species-specific
Care level
Intermediate
Adult size
Unknown at group level — colonies range from small clumps to more than 1 m depending on species
Expected lifespan
Potentially decades under stable conditions; colony age is open-ended because living fragments can continue the same genet, so a fixed aquarium maximum is not defensible.
Minimum housing
At least 100 L for small captive colonies; more space is required as colonies expand
Temperature
24–27 °C
pH
8.0–8.4
Hardness / minerals
Alkalinity 7–11 dKH; calcium 380–450 mg/L; magnesium 1,250–1,400 mg/L
Salinity
33–36 ppt; specific gravity about 1.024–1.027
Lighting
Species-specific, commonly about 50–200 PAR after gradual acclimation
Placement / zone
Lower to middle reef structure or a stable sand bed where the identified species permits
Filtration
Use mature reef biological filtration with skimming and removable mechanical capture. Maintain measurable balanced nutrients, prevent detritus lodging between polyps and size export for the growing colony and any supplemental feeding.
Aeration
Maintain strong whole-system gas exchange through surface movement, overflow and skimming while using broad indirect flow around the colony. Avoid direct tissue-blasting jets and stagnant pockets.
Maintenance
Check temperature, salinity and alkalinity frequently; trend calcium, magnesium, nitrate and phosphate; remove settled detritus; inspect tissue, skeleton, mount and neighbours after lights out; and expand clearance as the colony grows.

Identity and search names

“Acan” is an aquarium-trade grouping, not a single taxon. It commonly includes Acanthastrea and Micromussa species; identify the coral before applying species-level claims.

Search names: acans, acan corals, Micromussa corals

Environment and housing

Stable mature reef with secure placement, moderate broad flow, acclimated light and generous clearance from neighbouring corals

Social structure: Sessile colonial coral

Feeding and nutrition

Feeding ecology: Photosynthesis plus small planktonic or meaty foods accepted by the polyps

Feeding routine: Optional targeted feeding once or twice weekly if the colony responds; avoid overfeeding

Breeding, reproduction or spread

Sexual spawning in nature; aquarium propagation by careful fragmentation where the species and colony condition permit

Parental care: None

Detailed care and app-ready planning

Identity scope
“Acan” is an aquarium-trade grouping, not a single taxon. It commonly includes Acanthastrea and Micromussa species; identify the coral before applying species-level claims.
Adult size and space
Colony spread is unknown at group level and ranges from small clumps to colonies exceeding 1 m in some species. Begin with at least 100 L and reserve substantial growth and aggression clearance.
Colony size and space
Colony spread is unknown at group level and ranges from small clumps to colonies exceeding 1 m in some species. Begin with at least 100 L and reserve substantial growth and aggression clearance.
Social structure
Sessile colonial animal. The colony expands by polyp growth and must be managed as one growing territorial unit rather than as an isolated frag.
Aggression and spacing
Assume meaningful contact aggression. Allow 10–20 cm or more and inspect after lights out because expanded tissue and mesenterial filaments may reach farther than the daytime colony.
Swimming zone or placement
Usually lower to middle reef structure or stable sand, depending on species and tissue shape.
Placement zone
Usually lower to middle reef structure or stable sand, depending on species and tissue shape.
Feeding ecology
Photosynthetic corals that can also capture fine planktonic and meaty foods.
Feeding plan
Feed only suitably small food when polyps are receptive, usually once or twice weekly at most. Remove uneaten food and protect water quality.
Water stability
Maintain 24–27 °C, pH 8.0–8.4, salinity 33–36 ppt, alkalinity 7–11 dKH, calcium 380–450 mg/L and magnesium 1,250–1,400 mg/L with minimal daily swing.
Habitat structure
Use secure support that prevents tissue abrasion, broad indirect flow and gradually acclimated light. Avoid detritus collecting between polyps.
Compatibility plan
Separate from other LPS, soft corals and SPS by enough distance for full night-time expansion. Prevent shading and direct flow blasting.
Breeding or reproduction plan
Fragment only healthy, correctly identified colonies with clean tools. Allow complete recovery and do not sell fragments under an unsupported species name.
Propagation plan
Fragment only healthy, correctly identified colonies with clean tools. Allow complete recovery and do not sell fragments under an unsupported species name.
Quarantine
Inspect tissue, skeleton, underside and frag plug for eggs, flatworms, nudibranchs, algae and other hitchhikers. Use a separate stable coral quarantine system.
Quarantine and pest inspection
Inspect tissue, skeleton, underside and frag plug for eggs, flatworms, nudibranchs, algae and other hitchhikers. Use a separate stable coral quarantine system.
Welfare checks
Check inflation, feeding response, tissue edge, exposed skeleton, colour, mucus, sediment accumulation and contact damage.
Biosecurity and release
Use documented legal provenance. Verify current BICON, Live Import List, CITES and state requirements. Never release coral, fragments, pests or aquarium water.
Biosecurity, sourcing and release
Use documented legal provenance. Verify current BICON, Live Import List, CITES and state requirements. Never release coral, fragments, pests or aquarium water.
Main risk
Incorrect trade-name identification can lead to wrong care, spacing and legal claims.
Adult projected load
As colony surface area increases, calcification demand, night-time respiration, space use, detritus interception and optional feeding load all rise. Plan dosing, gas exchange, nutrient export and physical access for the mature colony rather than the purchased fragment.
Filtration
Use mature reef biological filtration with skimming and removable mechanical capture. Maintain measurable balanced nutrients, prevent detritus lodging between polyps and size export for the growing colony and any supplemental feeding.
Aeration
Maintain strong whole-system gas exchange through surface movement, overflow and skimming while using broad indirect flow around the colony. Avoid direct tissue-blasting jets and stagnant pockets.
Maintenance
Check temperature, salinity and alkalinity frequently; trend calcium, magnesium, nitrate and phosphate; remove settled detritus; inspect tissue, skeleton, mount and neighbours after lights out; and expand clearance as the colony grows.
Overridable warnings
Non-overridable: do not ignore progressive tissue recession, bleaching, exposed skeleton, pest evidence or direct coral contact. A knowledgeable user may use different light, flow, spacing or dosing methods only after gradual acclimation and documented stability show that the colony is not being damaged.

Compatibility, welfare and risk

Compatibility: Allow 10–20 cm or more from neighbouring corals and check night-time expansion and mesenterial filaments

Welfare: Tissue recession, exposed skeleton, failure to inflate, bleaching or repeated contact damage require immediate investigation of stability, pests and placement

Main warning: The trade term “acan” covers more than one genus, and colour alone cannot establish identity

Biosecurity and release

Use legally sourced stock with traceable provenance. Check BICON, the Live Import List, CITES and state rules. Never release coral, fragments, pests or aquarium water.

Sources