Common name
Acropora millepora
Scientific name
Acropora millepora
Category
Coral
Group
Small-polyp stony corals
Environment
Marine reef aquarium
Origin
Broad Indo-Pacific distribution; shallow reef flats, lagoons and upper reef slopes
Care level
Advanced
Adult size
Colony growth is open-ended and may develop into a large branching or table-form structure; reserve substantial horizontal and vertical expansion space.
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 200 L in a mature, chemically stable reef aquarium
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
About 180–350 PAR after gradual acclimation
Placement / zone
Middle to upper reef with strong flow and growth clearance
Filtration
Use mature reef filtration with efficient skimming, controllable mechanical export and stable nutrient management. Do not strip nitrate and phosphate to zero, and size export and dosing for the colony’s increasing calcification and feeding demand.
Aeration
Provide strong whole-system gas exchange through surface movement, overflow and skimming, plus broad random circulation around all branches. Avoid narrow jets that abrade tissue or leave stagnant inner-colony zones.
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

Species-level profile for Acropora millepora. It belongs to a difficult species complex and may be confused with A. convexa, A. spathulata and A. prostrata.

Search names: millepora acropora

Environment and housing

Mature stable reef with strong random flow, gradual high-light acclimation, secure attachment and clear space around the corymbose colony

Social structure: Sessile colonial coral

Feeding and nutrition

Feeding ecology: Photosynthesis plus dissolved and fine planktonic nutrition

Feeding routine: Maintain stable measurable nutrients; optional fine food in small amounts

Breeding, reproduction or spread

Sexual spawning in nature; aquarium propagation by fragmentation of established healthy colonies

Parental care: None

Detailed care and app-ready planning

Identity scope
Species-level profile for Acropora millepora. It belongs to a difficult species complex and may be confused with A. convexa, A. spathulata and A. prostrata.
Adult size and space
Reliable maximum colony size is unknown. Use at least 200 L and preserve space for a broad corymbose colony, strong internal flow and future pruning.
Colony size and space
Reliable maximum colony size is unknown. Use at least 200 L and preserve space for a broad corymbose colony, strong internal flow and future pruning.
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
Low direct aggression, but contact and shading cause damage. Allow at least 10–20 cm plus future branch growth.
Swimming zone or placement
Middle to upper reef with secure attachment and even light and flow across the colony.
Placement zone
Middle to upper reef with secure attachment and even light and flow across the colony.
Feeding ecology
Photosynthetic with dissolved nutrient uptake and capture of very fine plankton.
Feeding plan
Maintain stable low-but-measurable nutrients. Fine feeding is optional and must not create detritus or chemistry swings.
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 variation.
Habitat structure
Use strong broad turbulent flow, gradual acclimation to about 180–350 PAR and enough open space for water to pass through the colony.
Compatibility plan
Keep away from aggressive corals, prevent shading and maintain flow access as neighbouring colonies grow.
Breeding or reproduction plan
Fragment only a healthy pest-free colony with clean tools. Retain lineage and identification notes with every fragment.
Propagation plan
Fragment only a healthy pest-free colony with clean tools. Retain lineage and identification notes with every fragment.
Quarantine
Inspect for Acropora-eating flatworms, eggs, red bugs, nudibranchs, tissue recession and algae in a dedicated stable quarantine system.
Quarantine and pest inspection
Inspect for Acropora-eating flatworms, eggs, red bugs, nudibranchs, tissue recession and algae in a dedicated stable quarantine system.
Welfare checks
Check polyp extension, colour, growth tips, base tissue, pests, bleaching, flow through branches and rapid tissue loss.
Biosecurity and release
Use documented legal provenance. Verify BICON, Live Import List, CITES and state rules. Never release coral, fragments, pests or aquarium water.
Biosecurity, sourcing and release
Use documented legal provenance. Verify BICON, Live Import List, CITES and state rules. Never release coral, fragments, pests or aquarium water.
Main risk
Misidentification and rapid tissue loss following instability are the main risks.
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 filtration with efficient skimming, controllable mechanical export and stable nutrient management. Do not strip nitrate and phosphate to zero, and size export and dosing for the colony’s increasing calcification and feeding demand.
Aeration
Provide strong whole-system gas exchange through surface movement, overflow and skimming, plus broad random circulation around all branches. Avoid narrow jets that abrade tissue or leave stagnant inner-colony zones.
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: Prevent contact and shading; allow at least 10–20 cm plus future branch growth

Welfare: Bleaching, base recession, rapid tissue loss, tip burn or reduced polyp extension require immediate checks of stability, pests, flow and light

Main warning: A species complex and similar Acropora forms make colour-based identification unreliable

Biosecurity and release

Use legally sourced pest-free stock with traceable provenance. Check BICON, Live Import List and CITES requirements. Never release fragments or water.

Sources