Acclimatising, clam care and parameters are below.
By pouring half of your system water into the arrival bag with the clams, acclimate over at least a 10 minute period and more importantly, allow the clams to open slightly and start circulating the water. Place the clams in the system low down and avoid sudden high light levels. Move the clams into brighter conditions over a few days to allow them to adjust.
Giant Clams contain Zooxanthellae which photosynthesise and pass sugars to the clam. They require normal shallow reef conditions and parameters. Placing clams on the bottom of an aquarium long term is suggested only for shallow or very bright tanks. They require nutrients in the form of Nitrate or Ammonium, and trace elements. These are only needed in small amounts and are usually provided by having well fed fish producing waste in the system, or from manual addition.
Other than this, Giant clams do not need feeding in the aquarium. Whilst it is true they do have feeding mechanisms and have the ability to filter feed, there is evidence this is not required for them to thrive.
The main immediate threat to Giant Clams are predators in the system. The most problematic can be large Wrasse, Copperband and Long Nose Butterflyfish, Mantis shrimp, and large crabs. Hermit crabs and cleaner shrimp should be monitored. Over time, check your clams periodically for the small white cone shape snails known as Pyramidellid snails. They are 1-5mm, and parasitic. They can irritate and eventually kill the clam in increasing numbers.
Place clams on rock, not sand in their permanent location, preferably in a crevice. They will attach and this piece of rock can then be buried in sand if needed. Always face the clam towards the light source as much as possible.
Temp: 20-30 deg C
Salinity: 1.020 – 1.030
Enjoy your Perth Marine captive bred clams!