Everything I've read seems as though this is normal Ricordea Yuma behavior. Someone correct me if I'm wrong please.
I saw this on another site.
"Just an FYI, the 'bubbles' on the Ricordias are not polyps. Each Ricordia is one indivi dual polyp covered in bumpy growths. Some of those bumps can get quite large and balloon-like. One of mine has bumps that as large as my thumbnail and others (on the same rico) that are corkscrew-shaped."