Thats a beautiful FOX Squsihy. Mine was very small, but it opened up fully, and had 2 mouths on its one "bulb" (lack of a better term). I have had it for 6 months now, and i was hoping that it would split soon. I couple of weeks ago, i noticed a chunk missing from it when it opened up. 8O I thought that maybe i damaged it cleaning. So, i moved it to the bottom of my tank and left it alone. It started opening up again, and i could see that even though it was missing part of its upper portion, it still had both mouths intact. It never fully opened up again. Now i see that another huge chunk is missing from it AND its upper mouth is gone. There is only a little piece of it left.
What could have caused that? Do you think i should just put it out of its misery? Do i have a decorator crab hiding in my tank? How do i get rid of it if i do? I have a bunch of Nudis in my tank now (No idea where they came from) here is a pic: http://www.myaquaria.com/gallery/ackman/NudiCloseup
Do you think that they are the culprits?