How much light and flow does Crocea clam need?

Clam, very high light at roughly 300–450 µmol·m⁻²·s⁻¹ PAR, with high flow. Light and flow must match: high light with weak flow burns tips, strong flow with weak light thins the tissue.

Will Crocea clam attack neighbouring corals?

It shows no real aggression and can sit close to neighbours, though it still must not be shaded from above.

Does Crocea clam need feeding?

Optional. It survives without feeding, but regular small doses improve growth and colour.

What water parameters does Crocea clam need?

24–27 °C, specific gravity 1.024–1.026, 7–9 dKH, 400–450 mg/L calcium, 1250–1350 mg/L magnesium. That is only 2 dKH wide, so stability matters more than hitting a particular number.

Is Crocea clam a good beginner coral?

Difficulty: moderate. Growth: medium. Place it in the foreground / specimen. Spacing: place it on an exposed ledge or hollow with the mantle facing the light; it anchors itself with byssal threads and needs no tying down.

G-03 / 25Marine

Crocea clam五爪贝

Tridacna crocea · Tridacnidae

Crocea clam: the most light-hungry tridacnid, anchoring itself to live rock with byssal threads and colouring up from the zooxanthellae in its mantle.

Illustration to come

G-03 / 25 · Crocea clam Tridacna crocea

SpecificationsCoral atlas

Name: 五爪贝
Scientific name: Tridacna crocea
Family: Tridacnidae
Origin: Shallow reefs of the western Indo-Pacific, including Indonesia, the Philippines and the Great Barrier Reef
Type: Clam
Light: Very high light
PAR: 300–450
Flow: High flow
Aggression: No aggression
Feeding: Optional feeding
Alkalinity: 7–9 dKH
Calcium: 400–450 mg/L
Magnesium: 1250–1350 mg/L
Salinity: 1.024–1.026 SG
Growth: Medium
Placement: Foreground / Specimen
Level: Moderate

Water requirementsMarine

Temp.24–27 °C

pH8.1–8.4

Salinity1.024–1.026 SG

Alkalinity7–9 dKH

Units: temperature in °C, hardness in German degrees (dGH / dKH), marine salinity as specific gravity at 25 °C, volume in litres. These are the values recorded for the species and do not follow the site unit switcher.

Keeping notes

1Spacing: place it on an exposed ledge or hollow with the mantle facing the light; it anchors itself with byssal threads and needs no tying down.
2Flow: strong and chaotic but never a direct jet, which would keep folding the mantle back.
3Feeding: optional — adults live on light, while juveniles under 3 cm should get phytoplankton supplements.
4Water tolerance: it consumes calcium and alkalinity heavily, so hold calcium at 400-450 and dKH at 7-9 or the new shell edge stops growing.
5Growth form: the shell thickens and the ribs blunt with age, and the mantle shows its best fluorescence under strong light.

Frequently asked questions

How much light and flow does Crocea clam need?: Clam, very high light at roughly 300–450 µmol·m⁻²·s⁻¹ PAR, with high flow. Light and flow must match: high light with weak flow burns tips, strong flow with weak light thins the tissue.
Will Crocea clam attack neighbouring corals?: It shows no real aggression and can sit close to neighbours, though it still must not be shaded from above.
Does Crocea clam need feeding?: Optional. It survives without feeding, but regular small doses improve growth and colour.
What water parameters does Crocea clam need?: 24–27 °C, specific gravity 1.024–1.026, 7–9 dKH, 400–450 mg/L calcium, 1250–1350 mg/L magnesium. That is only 2 dKH wide, so stability matters more than hitting a particular number.
Is Crocea clam a good beginner coral?: Difficulty: moderate. Growth: medium. Place it in the foreground / specimen. Spacing: place it on an exposed ledge or hollow with the mantle facing the light; it anchors itself with byssal threads and needs no tying down.