I got a very nice used brake pressure bleeder from a guy...I think he
used it on a BMW.  The cap part screws right onto the Vanagon brake
fluid reservoir, and that on my 2002 Golf.  When I got it there was a
little residual fluid in it.  The fluid is sort of blue-green.  A
year or so has elapsed during which it has been in my not so dry
unheated garage.

So my question is how to get it ready to actually use.  I'm afraid
that blue-green fluid might be DOT5, which VW warns me even  a tiny
amount will contaminate my brake system and lead to
disaster.  Anybody know about colored brake fluid?  To get it cleaned
out, I will do the following:  Bring it into my nice warm dry house
for a week or so.  Put fresh new DOT4 fluid in it, swish it around,
flush it out, and repeat.  How many times should I repeat that, or
should I clean it with brake cleaner or something else?

Once I get this cleaned out and use it, how should I store it to
prevent moisture contamination in the future?

Thanks for any tips.
Edward