Just wanted to give an update about my clams. I've had similar situation as isseym328, cant explain it. I've lost 4 clams during all this. At first I was just giving the FWD every week to a week and half. Before actually starting the QT to get ready to dose with metro, on my last dip I lost my smallest maxima. So after the last dip, my crocea still had a bit of the edge of mantle curled. I then setup the QT and place them all in. It only had some pieces of live rock from my tank, with existing water from that tank. 5 gallons. the other 5 gallons was new make up water. After a week being in the QT the crocea's mantle was looking better. never dosed the metro. Its been a little over 5 weeks now in QT and 6 maxima's and 1 crocea are all looking great. I've even saw some new shell growth. Not sure if Im going to return them to the original tank.