Intro:
One of the most important reasons for the popularity of giant clams is surely their interesting coloration. The blue, green or golden color patterns that can be seen on the syphonal mantle of Tridacna crocea, T. maxima or T. derasa fascinate most reefkeepers. It is very unfortunate, however, that most of these colors are visible only if the clams are viewed from the same direction as the light that hits the syphonal mantle — the top. The more the angle of view differs from the direction of the light, the less color is evident on the clam. In the usual setup the clam is viewed through the front glass, although it receives illumination from the top. Under these conditions even a clam with a strong blue color and nice pattern will look quite brownish and the blue color will fade.
