Acropora millepora (Milli Acro)
Acropora millepora is a highly sought-after small polyp stony (SPS) coral renowned for its dense polyp extension and vibrant colouration. Commonly referred to as a “Milli”, this species develops compact, branching growth with a soft, fuzzy appearance created by its abundant, extended polyps.
 
Colour & Appearance
Acropora millepora is available in a wide range of striking colours, including bright pinks, deep reds, electric blues, greens and multi-tone combinations. Under strong reef lighting, particularly blue spectrum, its polyps often display contrasting hues to the base, creating exceptional depth and fluorescence.
 
Placement & Flow Requirements
This species thrives under high-intensity lighting and strong, turbulent water flow. Position in the upper half of the aquarium for optimal light exposure. Provide varied, random flow to encourage full polyp extension and healthy growth.
 
Care Level & Compatibility
Best suited to stable, mature reef systems, Acropora millepora is popular among SPS enthusiasts. With consistent parameters and proper placement, it grows steadily and adds vibrant movement and texture to SPS-dominated displays.
Water Parameters
Temperature: 24–26°C
Salinity: 1.024–1.026 SG
Alkalinity: 8–9 dKH (stable)
Calcium: 400–450 ppm
Magnesium: 1250–1350 ppm
 
Summary
Maintaining stable conditions is essential for strong colouration and sustained growth.
Acropora millepora combines intense colour, pronounced polyp extension and classic SPS structure, making it a standout addition to advanced reef aquariums.