Strange Leather Behaviour

[johnsmith]

Hi guys

our leather has started to act strangely even though still looks perfectly happy. It keeps expanding and curling out/under then going back to what was normal. Its difficult to describe but it just seems to "puff" up.

Any ideas?

Thanks

 

[SkiFletch]

Pics? Hard to say without seeing it...

 

[johnsmith]

Seems to have calmed down now and is back to normal. Been adding a few bits to tank recently which may have upset him.