Guys
This couldn't be simpler - this is what I use with my Moth cleaner:
1 part of Iso Propyl Alcohol
Your chemist/pharmacy can order this for you in 500ml containers
4 parts of the purest water you can find
Once again your chemist can help - mine comes in 2.5L containers.
Then - the mixing ritual:
1. Pour out 500ml of the water using your Mrs' best pyrex measuring jug and discard (the water, not the jug...)
2. Pour the IPA into the water container.
...then add a couple of drops of photograph wetting agent (this ensures the liquid spreads over the surface properly and doesn't "bead up")
Finally, give the water container a good shake to make sure everything has mixed nicely.
R.