I like to mix ink, and I want many cheap pens that I can use for my concoctions. I was thinking about buying a 10 pack of the Hero 616 pens. But do you have to fill it from a bottle? What I generally do with the regular "piston type" converter pens is mix the ink up in a water bottle cap and suck it directly into the converter. I'm not sure if this is possible with the Hero 616. I generally only make .5 millilitres at a time. So yeah, I know this is a newbie question, but is it possible to suck that small quantity of ink into the sac? Thanks.