Very good article, tested with pellet size "small" for reef tank of 400l, set minimum amount: configurable distrib 1 to 4 times per day with 1 or 2 rotations of the drum (1 minute intervals). One small problem: I had to stick a kind of small slide for the fall away from the edge of the pellets because I have a window of about 4cm inside of the aquarium that touches the surface of the water (RedSea aquarium Max). I also back the illumination lamp (rail). If not satisfied with my purchase after 1week of daily use