Cory dora that has lost his barbels

[witchone1973]

My tank is 80 Litre, it is home to 2 corydoras, 3 rummynoses and 5 platys. It has been running for 8 months, after being cycled. One of my corydoras has lost his barbels. Anybody have any possible ideas as to why.

 

[Flossie]

what is your substrate? I've read some sand or gravel can be sharp and cause them to loose their barbels