Design and simulate a controller for biomass in MATLAB SIMULINK

I am doing my dissertation on wastewater treatment and my methodology is that i have an equation for modelling the bioreactor. And i want to
1- model this bioreactor
2- evaluation of its performance
3- design a controller to control the concentration of biomass
4- a simulation for this model must be done using MATLAB SIMULINK

This project will focus on the biological wastewater treatment

I need anyone that can help me do the above tasks.

Kind regards