T. maxima pinched mantle
 

I'm not sure if what my T.max has is a pinched mantle or something else. Part of the mantle is sort of bunched up or scrunched up.

I'd try a FW dip but the clam is attached to an integral part of the reef rock structure (possibly an 8lb rock). Removal of the rock is a very dire option.

Is it worth trying to remove the clam from the rock for a FW dip? I fear damage to the byssal gland will prove fatal or something.

Need to do some more research before I commit to any plan of action, but, I'd love to hear any thoughts about the FW dip. Are there any alternatives?

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There is a type of weird algae, looks somewhat like a red bryopsis, growing on the shell. I am wondering if it's possible that the scrunching is simply the mantle being irritated by the algae. Just in case this is a possibility, I took a razor blade and scraped the algae off near the shell edge.

I wasn't able to get a good picture tonight, will try again tomorrow and post what the clam looks like.

I had a derasa that had a squished up piece of mantle and it turned out there was a snail in there.

Inside the clam? Did you have to pull it out yourself or did it come out on its own?

The FW dips have alway's helped my clams in the past Tony. 30 min does the trick.

If you can't get the clam out I would take a tooth brush and scrub it's shell tips. Play with the clam to get it to close first then scrub.
I did that on one of my maxima's before and that helped.

How long before you noticed a difference? I did try that tonight so hopefully it will look a little better tomorrow. Time will tell ......

Not sure how I'm going to rid myself of the red stringy bryopsis stuff, it's totally integrated into the flukes. The toothbrush didn't seem to scrape it off, but with a fresh razor blade I was able to cut some of it back.

The snail was inside. I first noticed the pinched mantle, watched it for a few days, eventually saw the snail on the outer inside edge of the shell but everytime I went to grab it with tweezers the clam would close. At this time the clam still looked healthy but within a few days of first noticing the snail the clam was dead. When I was able to get the snail out to get a looked at it I was able to identify it as a known clam killer. I have no idea what it came in on, never saw it before and haven't seen one since.

You could try doing a good water change first. That has helped me in the past and then if that didnt work then go to the F.W dip