← Plants & livestock

Marine Invertebrates

ORA Ultra Gold Maxima Clam

Tridacna maximaTridacnidaeClams

Add from My tanks →

1 photos

The ORA Ultra Gold Maxima Clam (Tridacna maxima) is an aquacultured clam graded Ultra Gold for its rich golden mantle colors, which shift as the mantle is viewed from different angles. It is peaceful and requires high light (250-350+ PAR) placed high in the tank near the lights, moderate flow, and stable clear water with calcium and alkalinity supplementation as it grows; it can reach nearly 12 inches in size.

Quick facts

Identity

Also known as
Small giant clam; Elongate clam; Gold maxima
Synonyms
Tridacna elongata; Tridacna maculata
Environment
Saltwater
Native to
Red Sea, East Africa, India, Southeast Asia, China, Australia, Polynesia, Indo-Pacific
Habitat
Shallow, clear, high-current reef flats and reef slopes, often attached to rock or rubble in high-density aggregations
Sourcing
Both
Conservation
Not Evaluated

Care

Care level
Moderate
Temperament
Peaceful
Adult size
1.5 – 8 in (3.8 – 20 cm)
Lifespan
10 – 20 yrs
Min tank
40 gal (151 L)
Growth rate
Slow
Placement
Top

Water

Temperature
75 – 78 °F (24 – 26 °C)
pH
8.1 – 8.4
dKH
8 – 12 dKH
Salinity
1.023 – 1.026 SG
Flow
Moderate

Behavior & compatibility

Social
Solitary
Aggression to own kind
Low
Active
Daytime
Reef safe
Yes
Invert safe
Yes
Shrimp safe
Yes
Clean-up role
Filter feeding
Population boom risk
Low

Feeding & breeding

Diet
Photosynthetic
Foods
Phytoplankton, Zooplankton
Breeding type
Broadcast spawner
Breeding difficulty
Not bred in captivity
Sexing
Simultaneous hermaphrodite; not externally sexed
Target feeding
Beneficial

Something wrong or missing? Submit a correction

Care guide

Overview

Reaching roughly eight inches over a decade or more of slow growth, this Ultra Gold selection carries a golden mantle whose tone shifts with viewing angle. It needs intense lighting placed high in the tank, moderate steady flow, and stable calcium and alkalinity as the shell thickens with age.

Care

Maxima clams need very bright, full-spectrum lighting placed high in the tank close to the fixtures, since most of their nutrition comes from the zooxanthellae housed in their mantle tissue. Moderate, steady flow is preferred; strong direct flow can cause repeated closing and stress. Water quality must be kept nearly pristine, with undetectable ammonia and nitrite and very low nitrate and phosphate, along with stable calcium, alkalinity and magnesium to support shell growth. This species is considered more demanding than other Tridacna species and is best suited to established, mature reef systems.

Feeding

The bulk of daily energy comes from photosynthesis via symbiotic algae, so consistent, intense lighting matters more than direct feeding. Dosing live phytoplankton periodically can supplement growth, especially for smaller or newly acquired individuals still adjusting to tank conditions. No target feeding is required once the clam is established under adequate light.

Tank mates

Avoid fish known to pick at clam mantles or siphons, including certain wrasses, triggerfish, puffers, and some large angelfish. The clam itself is peaceful and poses no threat to tankmates. It pairs well with other photosynthetic reef life once its lighting and placement needs are met and it is left undisturbed after attaching.

Breeding

Tridacna maxima is a broadcast spawner and simultaneous hermaphrodite in the wild, releasing eggs and sperm into the water column during mass spawning events. Captive spawning is essentially never observed in home aquaria, though commercial hatcheries such as ORA propagate this species using controlled spawning and larval rearing techniques. Home aquarists should not expect or attempt to breed this species.

Health

Newly introduced clams, especially smaller individuals under two inches, are prone to bleaching or tissue damage if placed under overly intense light without gradual acclimation. Sudden closures unrelated to feeding or disturbance can signal poor water quality or predation attempts by fish or pyramidellid snails. Byssal attachment should be allowed to occur naturally and never forced or cut away except as a last resort with a clean blade.

Sources

  1. Maxima Clam | Tridacna maxima | ORA | Oceans, Reefs & Aquariums
  2. ORA First Grade Maxima Clam - ORA - Bulk Reef Supply
  3. Maxima Clam First Grade, Aquacultured – LiveAquaria
  4. 3 Tips for Keeping Maxima Clams | Tridacna Clams | AlgaeBarn

Varieties in the catalog

More Clams

Something wrong or missing? Submit a correction

In the community

No public tanks are showcasing ORA Ultra Gold Maxima Clam yet.