Sudden mass crab death

[BTimms]

In the last three to four days I have lost 8out of 10 hermit crabs. All fish, snails and coral are fine and happy.

My parameters are level. No swings of any kind have been noticed.

what the heck!?

 

[Marronclownfish2008]

How old where they

 

[BTimms]

How old where they

Approximately 6 months to one year in my tank.

 

[JGT]

You sure they died and not their molts. Almost indistinguishable.

 

[HeyLookItsCaps]

Very odd, i would guess one of a few things. 1 would be salinity, hermits can croak while other inhabitants don’t at low levels 1.022 and below. 2 would be another inhabitant going for them, mantis, wrasse etc. 3 would be hermits getting into a house hunting death match, they can be quite deadly if they want a new shell. Lastly possibly copper?

 

[BTimms]

You sure they died and not their molts. Almost indistinguishable.

Yeah. It Ismail possible that they melted and hid. I now have three of 10. It’s so weird.