Crayfish molted and ate whole shell!

bulrush · Post by **bulrush** » Fri Aug 19, 2005 5:21 am

I have 2 (likely o. virilis) crayfish in a 10g tank. The larger one molted the other day. He is about 6" head to tail. After about 3 days I noticed his exo was gone. He must have eaten it. I didn't know crayfish ate the shell to recover nutrients from it. I did know hermit crabs did that.

Has anyone else seen this behavior?

The first 24 hours the crayfish seemed tired. After that the exo started disappearing. Perhaps it is easier to eat after 1-2 days, then they eat it.

Shanna · Post by **Shanna** » Sun Aug 21, 2005 9:33 pm

My blue crayfish do this all the time. This is normal behavior. They are recycling calcium they need in order to grow.

CanadianCray · Post by **CanadianCray** » Mon Aug 22, 2005 6:08 am

100% normal. They will eat the shell IF they need the nutrients. If your water is hard they can absorb the calcium & other minerals from the water so have no need to eat the shell. What ever isn't eaten after 4 days should be removed.