We are just full of clam posts today. This latest one features a video from our pal, Gerald Heslinga, a clam expert and founder of Indo-Pacific Sea Farms. In the video, Gerald discusses clam morphology, looking specifically at the size of the byssal openings as a probably factor common to clam deaths in the aquarium. Three species are examined in the clip, Tridacna crocea, T. maxima and Hippopus hippopus.
Each of these clams differ in the size of their byssal openings. Crocea clams have the largest opening, as they use it to dig into calcium carbonate rocks for protection. Maxima clams also have a large opening, though it is somewhat smaller than that if the crocea. They also dig into the rocks, but only slightly. The Hippopus clam has little to no opening, as the shell forms nearly interlocking grooves that allowed it to close very tightly.
How do these opening relate to clam deaths? Well, the smaller the opening, the less exposed surface area for pests, parasites, and predators to get at. Crocea and maxima clams have a fairly high mortality in the aquarium hobby and mariculture facilities, and according to Gerald, the Hippopus clams tell quite the opposite story.
Looking back on all the stories we’ve heard about random clam deaths throughout the years, Gerald’s assertions that clam death is related to byssal opening size does make sense. Too often, hobbyists would put crocea and maxima clams in the sand, instead of up on the rocks where their byssal openings would be less exposed.
That said, putting a clam on the proper substrate in your armed tank doesn’t guarantee success. There are still plenty of pests that can attack and kill a clam regardless of where they’re placed. Not to mention, the water conditions still need to be ideal for clam survivability.