IME the Iwaski and mak4 make the same noise. I have both. The Iwaki maybe a little better but not by much. I've flooded my iwaki and had to have it reapaired. My Mak4 dried out and started back up.... luck I guess. But IMO I would rather have an ampmaster= quiet. Mag pumps are good in sump out of sump more noise and they add heat to your tank. But thats not to bad unless you have 3 and no chiller