Why did my CB Golden Jawdropper Acropora lose its golden tones after increasing light?

Acropora tenuis colors depend on spectrum and nutrients, not just PAR. Keep strong blue-violet (420–470 nm) with modest white. Avoid “ultra-low nutrient” conditions; aim for nitrate 5–15 ppm and phosphate 0.03–0.08 ppm. Maintain stable alkalinity (7.8–8.6 dKH) and potassium ~390–420 ppm. Trace metals (iron, manganese) in small, monitored doses can support yellow fluorescence—verify with ICP before dosing.

How can I promote its signature branching without self-shading and tip burn?

Let it fully encrust before pushing PAR. Use high, chaotic flow that oscillates rather than a direct jet at tips. Periodically trim inner branches to open channels and prevent tissue loss at the base. Mount on a pedestal or isolated rock to keep light around the colony’s lower half. Increase light gradually (10–15% weekly) to avoid burnt tips.

Are there pests this tenuis morph is especially vulnerable to, and how do I catch them early?

Acropora-eating flatworms often target tenuis; look for crescent bite marks and pale patches between corallites. Dip new frags and inspect undersides with a flashlight 1–2 hours after lights out. Red bugs reduce polyp extension and color richness. Quarantine all Acropora, employ wrasses (e.g., Halichoeres) as sentries, and use targeted treatments only after confirming pests to avoid stress.

My colony is receding from the base while tips look fine—what should I adjust first?

Improve turbulent flow to the base to reduce detritus and boundary layer buildup. Nudge nutrients upward if near zero. Verify alk stability (daily swings trigger STN), and check for shadowing—thin or trim interior branches. Temporarily lower PAR 10–20% while correcting conditions. If recession continues, frag healthy tips ahead of the necrosis line and consider a short iodine dip.

CB Golden Jawdropper Acropora Coral

Acropora

Overview

CB Golden Jawdropper Acropora Coral shows bright golden branch tips with tightly spaced axial corallites. Acropora tenuis is a branching small-polyp stony coral that prefers strong light and moderate to strong, turbulent flow. It relies on symbiotic algae for most nutrition but will take fine particulate foods, which can support growth and color. Place high with good spacing from aggressive corals, and avoid shading or direct contact.

Quick Facts

Care Difficult

Lighting High

Flow High

Placement High

Temperament Semi-aggressive (short sweepers; 3–4 inches spacing)

Recommended Parameters

Temp 76–80°F

pH 8.1–8.4

Salinity 1.025–1.026

Calcium 420–450 ppm

AlkAlkalinity 7.5–9 dKH

Magnesium 1280–1380 ppm

Feeding photosynthetic (primary), microzooplankton, rotifers, copepod nauplii, coral-specific powdered foods, amino acids

Care & Placement

CB Golden Jawdropper Acropora Coral (Acropora tenuis) thrives with strong, stable conditions and consistent maintenance. Provide high light at 250–400 PAR with a gradual ramp-up to avoid bleaching; acclimate by reducing intensity 20–30% or using screen for 1–2 weeks. Deliver strong, random flow (gyre or alternating pumps) to keep polyps active and prevent detritus from settling; avoid direct, laminar jets that can damage tissue. Target fine foods 1–3 times weekly (rotifers, reef roids, oyster/copepod blends, amino acids) with nutrients kept modest: nitrate 2–10 ppm, phosphate 0.02–0.08 ppm. Keep temperature 75–79°F (24–26°C), salinity 1.025–1.026, pH 8.1–8.4, alkalinity 8.0–9.5 dKH, calcium 420–460 ppm, and magnesium 1300–1400 ppm. Test alkalinity and nutrients 2–4 times weekly until stable; consider ICP tests quarterly. Stability beats perfection—dose consistently and avoid rapid swings.Place frags in the upper third on a stable, clean rock with room to grow; allow 3–4 inches from other SPS and much more from aggressive LPS. A. tenuis grows quickly, encrusts, and can shade neighbors. Temperament is peaceful but competitive for space. Dip, inspect, and quarantine to avoid pests (AEFW, red bugs); drip acclimate 20–30 minutes and match temperature. Watch for paling (excess light/low nutrients) or tissue recession (alk swings, pests, low flow). Increase random flow, correct parameters slowly, and maintain export via skimming/refugium. Frag with clean cutters and secure with reef-safe glue once encrusted.

FAQ

Frequently Asked Questions

About the CB Golden Jawdropper Acropora Coral

Why did my CB Golden Jawdropper Acropora lose its golden tones after increasing light?

Acropora tenuis colors depend on spectrum and nutrients, not just PAR. Keep strong blue-violet (420–470 nm) with modest white. Avoid “ultra-low nutrient” conditions; aim for nitrate 5–15 ppm and phosphate 0.03–0.08 ppm. Maintain stable alkalinity (7.8–8.6 dKH) and potassium ~390–420 ppm. Trace metals (iron, manganese) in small, monitored doses can support yellow fluorescence—verify with ICP before dosing.
How can I promote its signature branching without self-shading and tip burn?

Let it fully encrust before pushing PAR. Use high, chaotic flow that oscillates rather than a direct jet at tips. Periodically trim inner branches to open channels and prevent tissue loss at the base. Mount on a pedestal or isolated rock to keep light around the colony’s lower half. Increase light gradually (10–15% weekly) to avoid burnt tips.
Are there pests this tenuis morph is especially vulnerable to, and how do I catch them early?

Acropora-eating flatworms often target tenuis; look for crescent bite marks and pale patches between corallites. Dip new frags and inspect undersides with a flashlight 1–2 hours after lights out. Red bugs reduce polyp extension and color richness. Quarantine all Acropora, employ wrasses (e.g., Halichoeres) as sentries, and use targeted treatments only after confirming pests to avoid stress.
My colony is receding from the base while tips look fine—what should I adjust first?

Improve turbulent flow to the base to reduce detritus and boundary layer buildup. Nudge nutrients upward if near zero. Verify alk stability (daily swings trigger STN), and check for shadowing—thin or trim interior branches. Temporarily lower PAR 10–20% while correcting conditions. If recession continues, frag healthy tips ahead of the necrosis line and consider a short iodine dip.