I seem IIRC warmer water is best.

Hey, I posted . more than once, about this topic.  Mix it in a
concentrated alkaline solution.  Then dilute for storage or for use.
The Sulfite can go in after4 the Alkali (first) then Glycin.  The
alkaline solution should be so concentrated that the Glycin fizzes as
it hits the surface.  I found that this brought brown Glycin back from
the dead.

Report your procedures and results, please.

Robert Vervoordt, MFA

 As I intend to order some Glycin from P. Formulary, checking
into it's solubility was the thing to do.
 At Jackspcs I read that a 3% solution of sulfite at 60*F will
dissolve 12+ percent amount of the agent.
 At unblinkingeye I read that an acid or alkaline solution is
needed. Ordinarily an acid solution is best for long life.
 I'd suggest you try 1gr of the agent in 10ml of sulfite and
of bisulfite solution; both 3%. Start at room temperature.
If it dissolves very slowly, warm.
 That 60*F may be for a reason. That's a reasonable low indoor
temperature and glycin may come out of solution if at a higher
concentration. Just a thought.                              Dan

 Search Google for, glycin metol hydroquinone . You'll find a bunch
of glycin specific info at sites listed there.                   Dan