reactor

The biological reactor node — activated-sludge kinetics (nitrification, denitrification, oxygen demand).

This node is also where the modular ASM code lives: the ASM1 and ASM3 models are being written as interchangeable modules so that, in time, those separate stops can fold into this one reactor node — pick the kinetic model you need, on a single twin. The standalone ASM stops are the stepping stones; reactor is the destination.