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

The question asks about the minimum concentration of dissolved oxygen in water that is necessary for the growth of fish. Dissolved oxygen (DO) in water is crucial for the survival and health of aquatic organisms, including fish. It affects respiration and other biological processes.

Explanation:

• The minimum concentration of dissolved oxygen required for the survival and growth of most fish species is around 6 parts per million (ppm).
• Fish require a certain level of dissolved oxygen in water to effectively carry out their metabolic processes. Low levels of dissolved oxygen can lead to stress, reduced growth rates, and even death in fish populations.

Analyzing the Options:

• Option 1: 10 ppm – Although beneficial, 10 ppm is higher than what is generally required for the minimum growth.
• Option 2: 8 ppm – This is also higher than the minimum requirement but would support robust growth.
• Option 3: 12 ppm – This concentration is higher and ensures the exceptional growth of fish but not the minimum needed.
• Option 4: 6 ppm – This is the correct answer as it is the minimum concentration required to sustain fish growth.

Thus, the correct answer is 6 ppm.