Why does my Pacman Acropora (Acropora tenuis) fade from neon yellow with blue tips to dull green?

Color shifts usually trace to spectrum, PAR, and nutrient balance. Aim for 250–400 PAR under blue-heavy lighting (peak 420–460 nm), with stable nitrate 5–15 ppm and phosphate 0.03–0.08 ppm. Keep alkalinity steady (7.5–8.5 dKH). Low potassium or iron can mute yellow; verify via ICP (K ~380–420 ppm, very low Fe). Stability over weeks, not days, restores pigments.

How do I prevent tip burn or base recession when moving this coral higher in the tank?

Ramp PAR slowly (10–15% weekly), use a longer blue ramp at photoperiod start/end, and maintain strong, random flow—never a direct jet at the tips. Keep temp tight (24–26°C), alkalinity swings under 0.3 dKH/day, and avoid large water chemistry jumps. If the base pales, lower light slightly and increase flow across the encrusting rim.

What placement helps maximize color while minimizing self-shading as it grows?

Give 10–15 cm clearance on all sides and angle the frag so branches receive crossflow. This species forms dense corymbs; pruning interior branches improves light to the base. Place mid–high on a clean, wide plug or shelf to encourage a strong encrusting skirt before vertical growth. Adjust flow to tumble detritus from inner branches.

I’m seeing slow tissue necrosis on one side only—common for this coral. What’s the fastest save?

Stabilize parameters first, then frag 5–10 mm into healthy tissue beyond the recession line. Dip frags to exclude pests, mount on fresh plugs, and increase chaotic flow around the mother’s affected area. Check for AEFW bite marks or red bugs with a flashlight. Match new-frag lighting 20–30% lower for a week, and avoid large alkalinity corrections.

Pacman Acropora Coral

Acropora

Overview

Pacman Acropora Coral shows bright yellow to green branches with contrasting polyp tips. Acropora tenuis is a branching small-polyp stony coral that prefers strong light and high, turbulent water flow. It relies on symbiotic algae for most nutrition, but occasional small particle foods can support growth and maintain coloration. Place high on stable rockwork with space from aggressive neighbors, and keep conditions stable to avoid tissue loss.

Quick Facts

Care Difficult

Lighting High

Flow High

Placement High

Temperament Peaceful (2–3 inches spacing)

Recommended Parameters

Temp 76–80°F

pH 8.1–8.4

Salinity 1.025–1.026

Calcium 420–450 ppm

AlkAlkalinity 8–9 dKH

Magnesium 1280–1350 ppm

Feeding photosynthetic (primary), microplankton, rotifers, copepod nauplii, coral-specific powdered foods (e.g., Reef-Roids), oyster eggs, amino acids, phytoplankton (limited)

Care & Placement

Pacman Acropora Coral (Acropora tenuis) thrives under strong, stable conditions. Lighting: high intensity 250–400 PAR; acclimate with light ramping or a screen method over 1–2 weeks to avoid bleaching. Flow: strong, turbulent, and random; use alternating pumps to keep polyps clean and prevent detritus buildup, but avoid a direct, constant blast. Feeding: primarily photosynthetic, but benefits from 1–2x weekly small-particle foods (rotifers, reef roids, amino acids); you can pause the skimmer for 30–60 minutes during target feeding.Water: 24–26°C (75–79°F), salinity 1.025–1.026, pH 8.1–8.4, alkalinity 8–9.5 dKH (keep daily swing under 0.3), calcium 420–460 ppm, magnesium 1300–1400 ppm, nitrate 2–10 ppm, phosphate 0.03–0.08 ppm. Monitor with reliable test kits or probes and prioritize consistency; this species is sensitive to rapid alkalinity and temperature changes. Dose two-part or kalkwasser to match consumption. Placement: upper third of the tank on stable rock; start mid-level and move up after acclimation. Allow 5–8 cm (2–3 in) from neighbors; avoid contact with aggressive LPS sweepers and fast encrusters. Compatibility: peaceful but vulnerable to stings; keep with other SPS under similar conditions. Practical tips: dip and inspect new frags, quarantine 2–4 weeks, and use a frag rack for observation. Watch for paling (too much light), base recession (low flow or pests), and pests such as Acropora-eating flatworms; maintain strong export, clean pumps, and trim to prevent self-shading.

FAQ

Frequently Asked Questions

About the Pacman Acropora Coral

Why does my Pacman Acropora (Acropora tenuis) fade from neon yellow with blue tips to dull green?

Color shifts usually trace to spectrum, PAR, and nutrient balance. Aim for 250–400 PAR under blue-heavy lighting (peak 420–460 nm), with stable nitrate 5–15 ppm and phosphate 0.03–0.08 ppm. Keep alkalinity steady (7.5–8.5 dKH). Low potassium or iron can mute yellow; verify via ICP (K ~380–420 ppm, very low Fe). Stability over weeks, not days, restores pigments.
How do I prevent tip burn or base recession when moving this coral higher in the tank?

Ramp PAR slowly (10–15% weekly), use a longer blue ramp at photoperiod start/end, and maintain strong, random flow—never a direct jet at the tips. Keep temp tight (24–26°C), alkalinity swings under 0.3 dKH/day, and avoid large water chemistry jumps. If the base pales, lower light slightly and increase flow across the encrusting rim.
What placement helps maximize color while minimizing self-shading as it grows?

Give 10–15 cm clearance on all sides and angle the frag so branches receive crossflow. This species forms dense corymbs; pruning interior branches improves light to the base. Place mid–high on a clean, wide plug or shelf to encourage a strong encrusting skirt before vertical growth. Adjust flow to tumble detritus from inner branches.
I’m seeing slow tissue necrosis on one side only—common for this coral. What’s the fastest save?

Stabilize parameters first, then frag 5–10 mm into healthy tissue beyond the recession line. Dip frags to exclude pests, mount on fresh plugs, and increase chaotic flow around the mother’s affected area. Check for AEFW bite marks or red bugs with a flashlight. Match new-frag lighting 20–30% lower for a week, and avoid large alkalinity corrections.