Murder Mystery?

[Uzidaisies]

I had three emerald crabs. A couple weeks ago, I found two of them dead in the morning, a couple days apart. There’s plenty of algae and I feed generously, but slowed down on the night feedings directed at the crabs specifically, because of nutrient concerns. I thought they must have starved. the only part of the crabs that seemed to be eaten was the underside of their tail flap thing. I chalked that up to the cuc. Now I’ve realized I haven’t seen one of my hermits, shell or anything in about a week. This is a nano tank (14g) and I only had five hermits to begin with. The missing one had killed a snail and took the shell so he was easy to identify. On two or three occasions, I have heard a sound coming from the tank… sounds like tapping a nail on the tank glass. Not particularly loud. Tap tap.. tap tap tap. I’m not sure that it was the nights before I found the crabs dead. I feel like everyone was still alive the mornings after I heard it. I’ve seen hermits smacking their shell against another, and thought that might be the sound I was hearing, or maybe the hob was doing weird stuff. I’m starting to wonder if I might have a mantis shrimp hiding in here. What are the chances? There are little bits of hermit crab around the tank, but I’ve left a molt in there at least once so i thought those might be from that. I would expect a mantis to do more damage to the emeralds. I also am perplexed about not seeing the hermit shell, the only places I can’t see in this tank are under the sand and inside the rock. The rock is from Petco, and I believe is maricultured, but I’m not sure where.

 

[SlugSnorter]

I had three emerald crabs. A couple weeks ago, I found two of them dead in the morning, a couple days apart. There’s plenty of algae and I feed generously, but slowed down on the night feedings directed at the crabs specifically, because of nutrient concerns. I thought they must have starved. the only part of the crabs that seemed to be eaten was the underside of their tail flap thing. I chalked that up to the cuc. Now I’ve realized I haven’t seen one of my hermits, shell or anything in about a week. This is a nano tank (14g) and I only had five hermits to begin with. The missing one had killed a snail and took the shell so he was easy to identify. On two or three occasions, I have heard a sound coming from the tank… sounds like tapping a nail on the tank glass. Not particularly loud. Tap tap.. tap tap tap. I’m not sure that it was the nights before I found the crabs dead. I feel like everyone was still alive the mornings after I heard it. I’ve seen hermits smacking their shell against another, and thought that might be the sound I was hearing, or maybe the hob was doing weird stuff. I’m starting to wonder if I might have a mantis shrimp hiding in here. What are the chances? There are little bits of hermit crab around the tank, but I’ve left a molt in there at least once so i thought those might be from that. I would expect a mantis to do more damage to the emeralds. I also am perplexed about not seeing the hermit shell, the only places I can’t see in this tank are under the sand and inside the rock. The rock is from Petco, and I believe is maricultured, but I’m not sure where.

Could be some parasite? if its just the crabs dying in your tank it could be.

anything else live in the tank? It could maybe be a mantis or a pistol, and is dragging things to a burrow, check for burrows or crevices.

Did you add anything new to the tank?

Maybe the params weren't suitable for a proper molting and they died?

EDIT: make sure the dead crabs aren't molts as TriggerFinger said

 

[TriggerFinger]

Emerald crab molts can look exactly like a whole crab. I’ve been tricked many times by my own. I have 2 porcelain and 3 emeralds and rarely see them. I honestly see more molts than the crab itself. Your hermit likely killed the snail for the bigger shell.

 

[SlugSnorter]

Emerald crab molts can look exactly like a whole crab. I’ve been tricked many times by my own. I have 2 porcelain and 3 emeralds and rarely see them. I honestly see more molts than the crab itself. Your hermit likely killed the snail for the bigger shell.

OP probably removed the dead crab from the tank, molts don't have any meat on them and are distinct from a full crab

 

[Uzidaisies]

Two clowns, and now four hermits, one emerald crab, a few Astrea snails, and eleven Ceriths. No additions in the couple weeks preceding the crab deaths, but the tank is just under three months old.

 

[SlugSnorter]

Two clowns, and now four hermits, one emerald crab, a few Astrea snails, and eleven Ceriths. No additions in the couple weeks preceding the crab deaths, but the tank is just under three months old.

check to make sure the dead ones were't molts, and check params to make sure the crabs could molt, after that Its investigation time

 

[Uzidaisies]

Emerald crab molts can look exactly like a whole crab. I’ve been tricked many times by my own. I have 2 porcelain and 3 emeralds and rarely see them. I honestly see more molts than the crab itself. Your hermit likely killed the snail for the bigger shell.

Thank you, yes, I inspected the crabs, not molts. The hermit did kill one of the Astrea snails and took the shell a while back. But now that same crab is gone.

 

[SlugSnorter]

Thank you, yes, I inspected the crabs, not molts. The hermit did kill one of the Astrea snails and took the shell a while back. But now that same crab is gone.

the crab killed the snail for the shell which is a little rare but not that unheard of. Check to see if the shell is is somewhere in the tank, or if sand is displaced (by potential killer or the crab buried itself to molt)

 

[Rick's Reviews]

Maybe a midnight investigation to see and count up who's out on a scavenger hunt

 

[Uzidaisies]

Maybe a midnight investigation to see and count up who's out on a scavenger hunt

Yeah, I often look in there around 11 pm to see if there’s anything I haven’t noticed yet. I want to take a look sometime at like 2am.

 

[SlugSnorter]

Yeah, I often look in there around 11 pm to see if there’s anything I haven’t noticed yet. I want to take a look sometime at like 2am.

gimme some updates! also some stuff is blind to red light so maybe use that if youve got it

 

[Uzidaisies]

gimme some updates! also some stuff is blind to red light so maybe use that if youve got it

Haha, I was thinking about trying the red light tonight. I actually thought I heard the sound a little while ago, I’ll have to do a headcount in the morning. There’s a hole at the bottom of a rock that looks like it could be a good burrow, so I’m keeping an eye on that area. I will let you know if I find any more evidence!

 

[SlugSnorter]

Haha, I was thinking about trying the red light tonight. I actually thought I heard the sound a little while ago, I’ll have to do a headcount in the morning. There’s a hole at the bottom of a rock that looks like it could be a good burrow, so I’m keeping an eye on that area. I will let you know if I find any more evidence!

mild test: cover it with sand, if its moved out something came through

 

[gia]

I had the same thing happen with two of my turbo snails a couple weeks ago. Found their shells with only black goo deep inside. Have no idea what happened. My other snails and small halloween crab, conchs and hermits are fine. Maybe they ate them?

 

[Uzidaisies]

I had the same thing happen with two of my turbo snails a couple weeks ago. Found their shells with only black goo deep inside. Have no idea what happened. My other snails and small halloween crab, conchs and hermits are fine. Maybe they ate them?

Certainly possible that the hermits did it. This hermit that I’m missing has killed two Astraea snails.(spelled it right that time lol)

 

[iamahab]

Certainly possible that the hermits did it. This hermit that I’m missing has killed two Astraea snails.(spelled it right that time lol)

My hermit crab is a straight up killer. Patrick the killer hermit crab. I've lost a turbo snail along with a few smaller hermit crabs to him. I ordered him some turbo snail shells he likes to switch out and it seemed to calm things down for now