Water Quality and Fish Tolerance

The video discusses key water quality parameters: pH, temperature, dissolved oxygen, and nitrates. It explains how pH levels affect aquatic life, the impact of temperature on cold-blooded organisms, the importance of dissolved oxygen for water health, and the role of nitrates in eutrophication. Each parameter is interrelated and influences water ecosystems.

What does a pH value of 7 indicate about water?

• The water is acidic.

• The water is highly alkaline.

• The water is neutral.

• The water is basic.

Which pH range is generally considered optimal for most fish?

• 3.8 to 5.0

• 9.0 to 11.0

• 4.0 to 6.0

• 6.5 to 8.2

How does the presence of iron in water affect fish tolerance to pH?

• Fish can tolerate higher pH levels.

• Fish die at lower pH levels.

• Fish can tolerate lower pH levels.

• Fish die at higher pH levels.

What is the effect of water temperature on cold-blooded aquatic life?

• They prefer temperatures below 0°C.

• They cannot survive below 0°C.

• They thrive in temperatures above 36°C.

• They can survive at any temperature.

Which factor does NOT affect water temperature?

• pH level of the water

• Depth of the water

• Color of the water

• Time of year

At what temperature do rainbow trout embryos die?

• Above 19°C

• Above 15°C

• Above 8°C

• Above 24°C

What is the maximum temperature at which largemouth bass can spawn?

• 27°C

• 34°C

• 32°C

• 21°C

How does temperature affect dissolved oxygen levels in water?

• Higher temperatures increase dissolved oxygen.

• Higher temperatures decrease dissolved oxygen.

• Temperature has no effect on dissolved oxygen.

• Lower temperatures decrease dissolved oxygen.

What is the minimum dissolved oxygen level required for a healthy fish population?

• 3.0 parts per million

• 2.0 parts per million

• 5.0 parts per million

• 4.0 parts per million

What is eutrophication?

• A process where water becomes too acidic.

• A process where water temperature increases.

• A process where algae growth decreases dissolved oxygen.

• A process where fish populations increase rapidly.