Clam with Broken Hinge Ligament
I am writing to you today seeking advice on my T. derasa. About a month ago, while cleaning my 125 gallon reef aquarium, I picked up my T. derasa to move it aside to scrape the glass. The clam didn't react right away and kind of "slumped" in my hand. When it finally reacted, it's shell was out of alignment and I believe it tore it's inner and outer ligaments with the force of it closing.
If that is the case, the ligaments have surely been weak I have seen those weak ligaments in aquarium grown clams, and I have heard of broken ligaments from some reefkeepers. The exact cause for this is unknown, but I suppose that a deficiency of an important substance during the process of growth in the aquarium is causing the ligaments to get brittle.
Since that time it has not been able to sit upright. It will slide to one side, not being able to hold it's shell together at the bottom. I made a support for the clam hoping that it would be able to repair it's ligament on it's own, but this has been to no avail.
I cannot imagine that the clam will be able to repair its ligament in any way. But on the other side I see no reason why it should be a disaster for the clam, as long as it will not be in a position where a permanent pressure pulls one shell valve away from the other one. If you can find a rock with an oval indention, where the clam fits in well, you can try to place it inside.
If you don't have that type of rock, you may try to glue some smaller rocks together trying to form a substrate with an oval indention in appropriate size to take up the clam.
Another possibility would be to try replacing the missing ligaments. With the help of underwater epoxy or hot melt glue you can make two fixation points (meaning to apply some of the epoxy/glue) on the shell valve near the anterior end (the hinge end of the shell valves). On those fixation points you can connect a kind of 'artificial hinge'. That could be any material that is flexible and will be held by the glue, like a piece of a thin nylon cable tie.
Underwater epoxy is easier to use, but it needs some scales or other physical structures to hold. In T. derasa you will probably not find any structures since it is quite plain. In that case hot melt glue will probably work better, as long as the shell surface is absolutely dry. To reach that, you can take the clam out of the water, dry the shell valves manually and leave it out of the water for a one or two minutes, until the shell valves are dry.
Just be careful about the position you choose for the artificial ligament, because it should more or less resemble the natural hinge. It should not restrict the shell valve movement, but on the other side it should also give enough support.
If you use hot melt glue, submerse the clam right after applying each part of the glue, so the glue will be cooled by the water and the heat will not pass the shell to reach the soft tissue of the clam.
Best regards to your clam.
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