Clam wont open all the way. Seems healthy

blackz151 · Feb 19, 2015

hart24601 said:
If it's really 6" I wouldn't expect it to attach. They are pretty heavy by that point and I have never had a maxima above 5" attach to anything. I would put it either on flat rock or sandbed where it won't fall over. A large and heavy clam falling from rockwork is enough to do some real damage to it.

I would be concerned about the lack of new growth. Possible that it's growing really slowly so it just takes a long time to notice, but in my experience growth is the only way to tell if a clam is doing ok. They can look absolutely fantastic for 2 months, but die the next day - generally if not a fast infection the only thing you will notice is the lack of new growth. Likewise I have seen really strange mantle extension and shells on clams that look terrible, but they were growing and doing just fine.

I will try to keep and eye on it and see if I can notice it getting any bigger. Thank you for the info on that I will look and see if I have a flat rock to put it on. Hes only just above the sand bed so If it falls its not to far to the sand.

hart24601 · Feb 19, 2015

No problem, good luck! One thing I have done in the past is to take a photo at night using a flashlight or a flash when they clam is retracted and you can see more of the shell. It's easier to look at this to check for growth, but don't obsess about it either, if you have it in the best spot you can there is not much else you can do!

blackz151 · Feb 19, 2015

Will it just grow longer? Or do they get wider as well.

hart24601 · Feb 19, 2015

Both, the shell also get thicker. What you should notice at night is around the shell opening where the mantle goes is bright white growth. It's hard to notice legnth and width growth, but not too hard to see the white at the top getting larger. There is a good photo, I think the 4th, that shows it here:

Reefs Magazine - The Basics of Giant Clam Biology and Care