Emerald Crab died after 2 weeks

[John-]

I got some bubble algea and learned emerald crabs will get rid of it. So I added one to the tank about two weeks ago. Some of the algea was going away, and it certainly stopped spreading, so though nmot gone, it definitly had been contained. Three days ago I added some corals that had been in QT for 40 days. I added a torch, a duncan and zoa's.
Today, I saw the crab around the top of the torch, and didn't think much of it. Checked a couple of hours later and he was in the same spot, so I poked him with a prong, and found out he was dead. I'd like an emerald crab in the tanks for bubble algae. But wondering what happened before adding another. Did he die of not enough food? Did the torch sting him to death? Any thoughts?

 

[shakacuz]

are you certain it died, and didn't molt/shed? They molt as they grow, and their old shell floats around until is decomposes/gets eaten by other crustaceans.

 

[John-]

Pretty sure he is dead. I have a shrimp that molts so I know what it looks like. His whole body is in tact. He does have some white specks on his shell.

 

[shakacuz]

Pretty sure he is dead. I have a shrimp that molts so I know what it looks like. His whole body is in tact. He does have some white specks on his shell.

maybe it was an old crab? can't ever really tell their age

 

[Fellowfishy]

maybe it was an old crab? can't ever really tell their age

 

[Fellowfishy]

I got some bubble algea and learned emerald crabs will get rid of it. So I added one to the tank about two weeks ago. Some of the algea was going away, and it certainly stopped spreading, so though nmot gone, it definitly had been contained. Three days ago I added some corals that had been in QT for 40 days. I added a torch, a duncan and zoa's.
Today, I saw the crab around the top of the torch, and didn't think much of it. Checked a couple of hours later and he was in the same spot, so I poked him with a prong, and found out he was dead. I'd like an emerald crab in the tanks for bubble algae. But wondering what happened before adding another. Did he die of not enough food? Did the torch sting him to death? Any thoughts?

Same thing happened today for me. He was all pale sitting in a new spot. He didn't move during feeding time, so I don't think he was molting. Hmmm??

 

[AlyciaMarie]

maybe it was an old crab? can't ever really tell their age

I'm thinking the same thing. Could have just been an old crab on his way out when you bought him. When I get snails for my tank, I always have one or two die within a few days/weeks, while the rest are fine.