Mantis Shrimp health

[Jay-rod20]

I am currently running a 29g biocube. Water levels perfect. Got a small peacock mantis last week, he had been at a local shop for about 4 weeks and was always active when I saw him up there. Picked him up, acclimated him to the tank and added some reef crabs to help feed and entertain him.

Dug himself a little cave under a rock and within about 2 hours he had taken out 5 of the crabs and seemed to be doing great. The next morning I noticed my heater wasn't set properly and the tank got down to 74 degrees and we couldn't find him. After moving a couple rocks, found him curled up underneath and wasnt moving. When I tried to move the rock off of him he sprang up and swan around for about 2 minutes and then rested behind a rock. Later that evening he was back underneath the rock I noticed him not moving under. The tanks temp is good now and has been for 2 days but he hasn't come out. I want to leave him alone if he's alive, but pull him if he's not. I just am not sure what's going on.

 

[Jay-rod20]

He is small, 2 inches, is this him about to molt?

 

[Flreefer]

A drastic change in temperature can shock all types of stock. If he went back under the rock on his own, I would just keep checking to see that he is still alive, and see if he survives.

I'm hoping that the LFS told you to be very careful near this shrimp. They are nicknamed "thumb-splitters" for a reason. Those 2 little clubs on the front of him pack a serious punch!!
When they strike, they create a water cavitation that you can hear, similar to a sonic boom. And believe it or not, can create light, with the force of their strike!! (Nat Geo special). Steer clear of him!!
Best Of luck, hope he comes around for you....fascinating creature.

 

[Jay-rod20]

Oh I am very aware of the danger of that amazing predator. That is the allure of them and the biocube/nanocubes are just perfect being acrylic.

If he just got stressed, I want to leave him alone, but I'm just not even sure if he is alive. I can just barely see his tail and it doesn't look like he's moved in about 48 hours. I'm just continuing to monitor the temp, and if he hasnt moved by tomorrow I might remove the rocks to see if he's living. Where he is would require me to move most of my rock out

 

[Flreefer]

At risk of sounding like a bad pet parent Lol, you could probably just gently poke him with a stick, to see if he reacts. He'll definitely move, if he's able.