Giant Clam
Tridacna sp.Bruguière, 1797Genus
Bivalve with brilliantly colored mantle. Photosynthetic and requires strong lighting. Jewel of the reef tank.
Names & Synonyms
- CommonGiant Clam
- Commonシャコガイ
- SynonymChametrachea
- SynonymDinodacna
- SynonymFlodacna
- SynonymPersikima
- SynonymSepidacna
Overview
Giant clams (genus Tridacna) are the world's largest bivalve molluscs, housing symbiotic zooxanthellae in their iridescent mantles to derive most of their nutrition from photosynthesis. Native to shallow reefs of the Indo-Pacific, Tridacna gigas can reach 1.2 m in length and 200 kg. Mantle coloration spans electric blues, greens, golds, purples, and browns, making giant clams prized display animals. Successful husbandry demands intense lighting (300–500+ PAR) and stable reef chemistry—calcium 400–450 ppm, alkalinity 7–11 dKH, and magnesium above 1280 ppm. Starting with juveniles (3–5 cm) eases acclimatization; large specimens are placed directly on the tank floor.
Care Specifications
| Temperature | 24〜27℃ |
|---|---|
| Specific gravity | 1.023〜1.025 |
| Salinity | 33〜35 ppt |
| KH (carbonate hardness) | 8〜12 dKH |
| Calcium (Ca) | 400〜450 mg/L |
| Magnesium (Mg) | 1280〜1350 mg/L |
| Lighting | High |
| Water flow | Medium |
| Placement | Bottom |
Care Points
- Lighting—Strong lighting essential (metal halide or powerful LED)
- Water Quality—Ca 400-450ppm, KH 7-11 required
- Placement—Upper tank where light is strongest
- Growth—Slow but steady growth
- Notes—Do not forcibly detach byssal threads
Regulatory & Conservation
- CITES:
- Appendix II
- Notes:
- シャコガイ科(Tridacna spp., 二枚貝)=CITES 附属書II(全種、1983/1985 掲載)。サンゴ目ではないが本カテゴリに混在。日本法は非該当。
Sources
- AlgaeBarn: Water Parameters 101(careSpec)
- NOAA Fisheries: Giant Clam Tridacna spp. CITES App. II(regulatory)
- Wikipedia(detail)
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