I got the one on the right for free form the LFS. I wanted a pic of him so I did a freshwater dip and low and behold another one about 3 times his size jumped out too. Still trying to get an ID. Here they are.
Er...Most saltwater animals can't stand freshwter so they try and run away to salt water.....simple like tht to expel movable animals from live rock...As for fish it cleans tem because the diseases they catch take water in so fast that when they go to freshwater they POP or die off