Carduus Acropora Care Guide
Carduus Acropora (Acropora carduus) is a SPS coral. Care covers 250-400 PAR, high flow, reef parameters and feeding; advanced level.
Compiled by Aquairi from published sources · Published · Updated
Overview
Carduus Acropora (Acropora carduus) is a SPS coral in the family Acroporidae. Bottlebrush Acropora with spiky radial corallites. Less common but visually striking.
Taxonomy
- Family: Acroporidae
- Genus: Acropora
- Scientific name: Acropora carduus
- Common synonyms: Spiny Acro
Habitat
In the wild, Acropora carduus is reported from Indo-Pacific, where it occupies shallow reef flats and upper slopes (typically 1-15 m). The species adopts a branching growth form on hard substrate within zooxanthellate reef communities.
Tank requirements
- Salinity (specific gravity): 1.025-1.026
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Carbonate hardness (dKH): 7.5-9
- Calcium: 420-450 ppm
- Magnesium: 1300-1400 ppm
- Phosphate (max): 0.03 ppm
- Nitrate (max): 5 ppm
- Minimum system age: 1 year
Placement and lighting
- PAR (placement zone): 250-400 PAR
- Water flow: high
Place this SPS coral on the upper rockwork where light is bright and water movement is strong, ideally turbulent rather than laminar. Acclimate gradually to high PAR over 2-3 weeks to avoid bleaching. SPS demand a mature system: stable alkalinity, calcium, and magnesium with phosphate and nitrate kept ultra-low.
Feeding
Acropora carduus hosts symbiotic zooxanthellae and derives most of its energy through photosynthesis. Additional feeding is generally not required when lighting is adequate.
Compatibility
This coral is passive toward neighbours. Reef-safe with most fish and invertebrates.
Care notes
Difficulty level: advanced. Reported skeletal growth in well-tuned reef tanks is approximately 0.4-0.9 cm/month. Propagation by fragmentation is straightforward for branching 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.
Acropora carduus Propagation Guide
Overview
Acropora carduus is a bottlebrush stony coral in the family Acroporidae, named for the spiky radial corallites along its branches. Like other Acropora it grows as a colony of small polyps sharing tissue over a calcium carbonate skeleton, with symbiotic Symbiodinium algae providing energy through photosynthesis. The bottlebrush branches are fragged at the tips like other SPS.
Reproductive Mode
Acropora reproduce sexually through gamete release and asexually when fragments reattach and grow into new colonies. Aquarium and farm propagation use fragmentation because each frag carries the parent's genetics and resumes growth once secured.
Fragging / Asexual Propagation
- Select a healthy, well-coloured branch tip from an established colony.
- Cut or snap the branch with bone cutters or a saw, keeping the break clean.
- Glue the frag to a plug or rock with cyanoacrylate or epoxy.
- Set the frag in moderate light and flow until tissue grows over the cut.
- Dip and quarantine new frags before introducing them to a display.
Under good reef conditions, finger-sized fragments can grow into much larger colonies within one to two years, so a single parent supplies many bottlebrush frags over time.
Conditions for Propagation
Fragments need stable conditions to heal. Acropora are especially prone to bleaching when stressed, which is caused by the loss of their zooxanthellae, so steady temperature, salinity, alkalinity, calcium and magnesium are critical. High light and high flow drive the dense skeletal growth this branching form needs.
Sexual Reproduction
In the wild, Acropora participate in annual mass-spawning, releasing gametes into the water for external fertilisation and larval development. This is rarely seen in home aquaria, so hobby propagation depends on fragmentation.