remember to give the whole thing 3 or 4 thin coats rather than one thick coating of paint!
then take a a bit of pure white and add this to your base color mix and start to squiggle this mix into the middle of all panels and flat surfaces on your tank and you should end up with it looking like this.
some of the pic's have been darkened a bit so you can see how the lighter paint goes on top of the base color.
...............cheers oz.
