"So that leaves dripping from the top or syringe filling. Dripping is tricky because you essentially need to flood the thing, but avoid getting liquid down the center, not a simple task. I had the best luck using a syringe with the needle placed between the side wall and the filler. I had to find a spot where the blunt needle would go all the way to the bottom and then slowly fill until I saw the top filler become saturated."
From a review........