The DŌS uses a direct drive mechanism that will not slip, it will not strip, it will not grind to a halt. On the other hand, many other peristaltic dosing pumps used for aquariums have gears that can (and do) strip. Or, worse yet, some pumps work by using the friction of rubber rollers on the smooth metal motor shaft to make the pump spin. Foreign matter like salt creep, additives, etc. often get into the drive mechanisms of these pumps and make them fail or pump unknown amounts.