I took more pictures (both in and out of the water) of the latest mystery creature as well as the new crabs on the block.
This picture shows the mysterious creature and the emerald crab hiding beneath the shell. The emerald crab hid in and under the shell the whole 4 hours it was acclimating.
The halloween hermit has been pretty calm during acclimation. He’s got an antenna peeking out of his shell since he’s now in the tank. I expect both new crabs to check things out and to forage some now that the lights are off for the night.