My arrow crab has been in my tank for exactly one week. I just looked in and he had just sort of collapsed over and died. ARGGGH! He was fine the whole week. Got adjusted pretty quick and was traipsing around the tank. I was worried that he wasn't feeding enough (didn't like Formula Two), so I put in a table shrimp strapped to a rock and he ate on that overnight the night before last. Seemed pretty happy about it too. I took the remains of the shrimp out yesterday morning. Today I came home from work and he was alive on top of the rock where he hangs out. I came back after a couple of hours and he was dead.
I took a good look at the body and can see nothing at all that looks suspicious other than he was missing the "thumb" off one of his claws. Could have happened when I pulled him out of the rock, but I'm not sure.
All my hermits are fine, the emerald crab is fine, the peppermint shrimp just came out to feed. I checked the parameters just now and Ammonia and Nitrite are zero. Nitrate is pretty much zero as well.
I have a 90 gal tank setup with a 30 gal sump, GAC and GFO reactors, Reef Octopus Skimmer, JBJ 1/4h chiller and a Vortech MP40.
Any ideas? I'm a new reefer and this tank is newly setup, but the rock is fully cycled (cycled it for 4 months actually, watched the cycle happen, and I know it's done....).
Are arrow crabs particularly sensitive to anything? Could it be stress from the move a week ago? Did he need to eat a bunch more?
I'm sad to lose my first animal and I'm worried about the rest....
Thanks in advance for any suggestions!