Does anyone have any experience reflowing tin?

A circuit board manufacturing facility is using a sulfonic acid based electrolytic tin solution.  They are plating tin over nickel as per their customer's spec.   The purpose of the tin bath is for reflowing purposes, not just as an etch resist.  However, after a few months the tin's capability of reflowing starts diminshing to the point of having to replace the bath.

Is there anyone else out there reflowing electrolytic tin?  Are they encountering the same issues?

Any input would be greatly appreciated.


Thank you,


Rene