Homebrew PCBs

Hi,

I have been using CuCl etchant for a while now. Before etching I add a
tablespoon of 100 volume H2O2 and away I go. Recently something has
changed. When adding the H2O2 the soulution used to bubble slightly and
change colour from muddy green to a nice blue-green. Recently when I add
the H2O2 it bubbles violently and nothing else happens. Has anyone else
had this problem?

Perhaps I should just dump the solution and start again.

Les