**4. Conclusions**

1. With the initial intermittent operation and the late continuous operation, the plant took 7 months to complete the start-up of biological iron and manganese removal filters.

2. By comparing the production filter and the filter column test, it can be inferred that although the intermittent operation reduced the backwashing frequency, no contribution was made to the cultivation of the biological manganese removal layer.

3. For the stopping operation of the biological filter in the start-up or stable operation stage, it is suggested to use filter emptying to ensure that the filter can be in an aerobic state, which is beneficial to the aerobic microorganisms and the biofilter layer.

**Author Contributions:** Formal analysis, H.Z.; Funding acquisition, J.Z. and D.L.; Investigation, H.Z.; Methodology, H.Z.; Project administration, J.Z.; Supervision, J.Z.; Writing—original draft, C.Y.; Writing—review & editing, H.Z.

**Funding:** We would like to gratefully acknowledge the National Natural Science Foundation of China (No. 51308009 and No. 51678006) and the Scientific and Technological Research Program of Beijing Municipal Education Commission project (KM201510005021) for financial support.

**Conflicts of Interest:** The authors declare no competing financial interest.
