When I picked up the four ghost shrimp I knew a little bit about the whole molting deal but since going down to two for the past few weeks things have seemed out of control. The one I have is huge, already bigger than my zebras at 2inches the other one that we use to call tiny is almost as big at the zebras, about 1inch. Between the two there is just about always a discareded shell in the tank - I've seen the shrimp picking at the shell so unless its there the next day I take it out but last week I had three shells. Exactly how often do these shrimp molt? Can't one molt twice in one week or do I have a third monster hiding from me?