So I have successfully kept a Derasa Clam for awhile, and wanted to try keeping a Maxima. I purchased one from saltwater fish. It did great for about 3 weeks and in one day it died. It didn't show any signs that it was going to die. I just came home for lunch was checking everything out and noticed the mouth was gaping and when I got home 4 hours later it looked all shrunken and was pretty much nothing. My water parameters are great. I had the clam placed in about the middle of my tank on my live rock. Any ideas on what could of happened?