Yep, I always rinse my tube with hot water then I pour hydrogen peroxide through it. ;-)
I use 4 tablespoons of coffee to 4 cups of distilled water and that gives me enough for 2 back to back CEs. I still haven't worked up to retaining the whole 4 cups, I find the 2 cup back to back easier.
Everyday is good, I need to get back to that for sure!