In this lesson, students will investigate and discover relationships among dissolved oxygen levels, pH, and temperature.

• Students will investigate and discover relationships among dissolved oxygen levels, pH, and temperature.
• Students will manipulate the levels of temperature and pH to determine the effects on dissolved oxygen, population and species richness in a freshwater system.

• dissolved oxygen
• pH
• temperature
• freshwater

A guided lesson video (optional) is also available for this activity. The video is targeted at students and designed to help guide them through the interactive exploration and the concepts covered within. (It may also be helpful for teachers who may be using the activity for the first time.) 

In this lesson, students will:

• Understand how the temperature of the water affects the dissolved oxygen levels.
• Determine the best water temperatures and pH levels for freshwater fish population numbers and number of species.