Selection
Now that you’ve created the right environment, it’s time to choose that beautiful specimen for your aquarium. Let's take a look at some of the ways to be sure you are getting a healthy and attractive specimen.
When examining Tridacnids, make sure that the mantle extends well over the shell. Also, the clam should show a healthy response behavior to stimuli. This is done by placing your hand between the light source and the clam. This should cause the clam to close quickly and re-open after a few moments.
Clams generally appear more attractive when viewed from the top than they do when viewed from the front of the aquarium. Many times, the colors will brighten when you place them under more intense lighting, and could fade under inadequate lighting. Do keep this in mind when evaluating a prospective Tridacnid for purchase.
Check to see if there is any “bleaching†or white areas on the mantle. This normally appears between the incurrent and excurrent siphon. Sometimes, this bleaching will appear brown or “washed out†in color, but don’t mistake a gold color as bleaching. The gold clam pictured above is not bleached.
Inspect the clam around the mantle and “byssus†(foot) to make sure there are no Pyramidellid (“Pyramâ€) snails. These parasitic snails can do serious damage to the clam and must not be allowed into your aquarium. Make sure that you carefully examine the specimen for the presence of jelly-like sacks which house the eggs of these snails. Several dozen snails can hatch simultaneously. If Pyramidellids are discovered in your aquarium, there are a few fish that will help in controlling them, such as Coris formosa, Coris gaimard, and the popular Sixline Wrasse, Pseudocheilinus hexataenia. Manually removing these pests at night (when they are feeding) may also be necessary.
Look for “gaping,†a condition in which the animal’s shell is completely open, the mantle poorly extended, and the incurrent siphon appears to be stretched. In most cases, this is caused by some form of stress. This is often caused by shipping, and in most cases will cease after a few days. Having kept and shipped thousands of clams, I have noticed that Tridacna crocea displays this condition more commonly than other Tridacnids. However, Tridacna crocea seems to recover from the condition whereas it is cause for concern in Tridacna maxima.
Check the shell to make sure it is not broken, and that the mantle is not torn or ripped. Do not purchase an animal that displays any signs of damage.
Prior to purchasing your clam, ask if the specimen was collected in the wild or if it was cultured. Usually cultured clams are easier to keep and maintain. One of the potential problems with wild-collected clams is the collection process itself. Improper collection techniques can result in serious damage to the clam, particularly the byssal gland. Carefully inspect your prospective purchase to assure that the byssal tissue is not torn or hanging from the specimen. This damaged tissue can result in the development of a bacterial infection that caused the clam to die.
If at all possible, find out how long the clam has been in the dealer’s inventory. Ask your dealer if you can purchase it and leave it in his/her tank for a few days longer. This extra time will allow you to observe the clam and make sure that no infections or other maladies manifest themselves before you take the animal home.