Gigas Clam (Tridacna gigas)
This majestic mollusk can weigh in at over 400 pounds, reach a length of almost four feet and live for over 100 years. Like most other clams, it filter feeds on phytoplankton through its gills and also receives nourishment from endosymbiotic algae that live in its colorful mantle. While they likely can live entirely off products from their zooxanthellae, filter feeding accounts for approximately 2/3 of the carbon required for growth and respiration in young gigas clams, whereas it accounts for only 1/3 in the mature adult’s diet. Because the symbiont provides most of the clam’s sustenance, it must have daily access to very intense light. Its mantle is very attractive, exhibiting many bright blue cat’s-eye spots over a rich golden background. Unlike its cousins, it cannot (especially as it matures) close its shell completely.
See below for more information.
Size and Care Requirements:
- Purchase Size: Approximately 5″ (length).
- Max Size: 120 cm (47 in).
- Water Parameters: 72-78° F, dKH 8-12, pH 8.2-8.4, sg 1.023-1.025.
- Color: Bright blue spots over gold background (mantle).
- Reef-Safe: Yes.
- Diet: Omnivore. Consumes phytoplankton as well as substances released from its zooxanthellae. This very large clam requires intense lighting and benefits greatly from the regular addition of live phytoplankton.
Gigas Clam Species Information
Of all the giant clam species, T. gigas has the widest distribution. This iconic bivalve inhabits the South Pacific and Indian oceans from the Philippines to the South China Sea and Borneo. The giant clam lives over shallow sand or rubble flats on or near coral reefs. In very clear waters it occurs at depths of over 60 feet.
This unusual clam is totally reef-safe. It should not be kept with certain predatory fishes such as triggerfish, puffers, certain wrasses, etc. A sustainable alternative to wild-caught gigas clams, these aquacultured specimens have a comparatively higher survivability.
Benefits of Captive Bred Clams
Captive-bred gigas clams provide a huge advantage over wild-caught specimens. Because they are cultured under captive conditions, they are better adapted to living in an aquarium and are more disease resistant. They are also better able to handle shipping stress. By buying aquacultured aquarium livestock, you support the sustainable farming of marine organisms and helping to make our hobby more sustainable!
AlgaeBarn keeps these gigas clams in an invertebrate-specific system to minimize the transfer of fish parasites and other unwanted hitchhikers.
100% Alive on Arrival (AoA) Guarantee
We guarantee that every gigas clam we sell will be Alive On Arrival and in good health. Should any arrive in any other state, we will either replace them free of charge (including shipping). If the total livestock loss is less than $40, we will issue store credit. For more information, please visit our 100% Alive On Arrival Guarantee page.