Homebrew PCBs

Hi guys,

I have been etching for a while now with ferric chloride.  Today I 
made up a different home brew based on information found on 
instructables.  This consists of two parts hydrogen peroxide and 1 
part muriatic acid.  The final step was to etch some boards which will 
eventually convert this mix to Cupric Chloride.

First, I was amazed at the speed of etching - very fast - even faster 
if you agitate the circuit board.  I didn't use a bubbler as  am not 
sure if I am suppose to.

So, with that experience under my belt, I got a couple questions

1) How will I know this is now Cupric Chloride?

2) Should I use a bubbler with Cupric Chloride?

3) Does Sharpie pen ink hold up as a resist?

4) With this, is there any gasses given off that I need to be aware 
of?

Any other advice or suggestions would certainly be appreciated.

Chris