A treatment train that removed iron perfectly last month can suddenly start passing manganese straight through the filter — same water source, same equipment, same operator — and the difference often comes down to one variable most people overlook: pH. Building on the basic oxidize-then-filter concept from Class D, this guide takes you into actual process control: choosing between aeration and chemical oxidants, understanding why manganese is so much more pH-sensitive than iron, running the oxidation-filtration train correctly, and troubleshooting the most common failure modes a Class C operator will encounter.
The Oxidation-Filtration Process Train
Removing iron and manganese is not a single unit process — it is a train of steps that each have to work correctly for the next one to succeed:
- Oxidant application — aeration and/or a chemical oxidant is introduced to convert