shrimp molting

They will do a lot of jumping around to get the shell/exoskeleton (I believe it is called) off. Some fishkeepers add iodine to help though I do not support this. You will see a close to perfect copy of its body once the shell is off and the shrimp is prone to going into hiding for a while since it feels vulnerable.
 
that can possible explain why i can't find any of the 10 i put in a while ago. i t would also explain these weird white things at the bottom of my tank
 
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