[jyl]

I think that is a good direction. A cheap peristaltic pump 12V, a wall wart, a timer switch, and a case. Figure out how many seconds to turn the switch to, for the desired dose, and write that on the case.

The other ideas could work but my wife is not going to like bags hanging around like I'm giving the dishwasher a transfusion. I'm already on thin ice with this d/w.