Name the two different categories of microbes naturally occurring in sewage water. Explain their role in cleaning sewage water into usable water.

Explanation

### Step-by-Step Solution:

1. **Identify the Categories of Microbes:**
The two different categories of microbes that are naturally occurring in sewage water are **bacteria** and **fungi**.

2. **Role of Bacteria and Fungi in Sewage Treatment:**
- **Bacteria:** They play a crucial role in breaking down organic matter present in sewage. They consume this organic material, which helps in reducing the Biological Oxygen Demand (BOD) of the sewage water.
- **Fungi:** They work in association with bacteria, forming a network known as **mycelia**. This association enhances the efficiency of the sewage treatment process.
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