Question

The minimum concentration (ppm) of dissolved oxygen in water that is required for the growth of fish is

• A. 10
• B. 8
• C. 12
• D. 6

Hint:

- Dissolved oxygen (DO) levels in water must be maintained above 6 ppm for healthy fish populations.
- Low DO levels can lead to hypoxia, which negatively affects aquatic life.
- Factors affecting DO levels include temperature, water pollution, and algal blooms.

Answer 1

The Correct Option is D

Step 1: Understanding Dissolved Oxygen (DO) in Water 
- Dissolved oxygen (DO) is essential for the survival of aquatic organisms, including fish. 
- The minimum required concentration of DO for fish growth is generally 6 ppm (parts per million). 
- If the DO level drops below this threshold, it can lead to stress and suffocation in fish populations. 

Step 2: Verifying the Correct Answer 
- The recommended minimum concentration of DO in natural water bodies for healthy fish growth is 6 ppm. 
- The other options (8 ppm, 10 ppm, 12 ppm) represent higher concentrations that are beneficial but not the absolute minimum required. 
- Thus, the correct answer is 6 ppm (Option 4).