In an experiment studying the effect of pH on algae growth, what should the student ensure?

In an experiment designed to study the effect of pH on algae growth, it is essential to use the same species of algae in all trials. This ensures that any observed changes in growth can be attributed to the varying pH levels being tested, rather than differences in the growth patterns or behaviors of different species. Using a consistent species allows for a controlled comparison, eliminating one of the major variables that could confound the results.

If different species of algae were used, they might have inherently different tolerances to pH changes, which would make it difficult to draw accurate conclusions about the impact of pH on growth. By holding the species constant, the experiment maintains focus on the primary variable of interest, leading to more reliable and valid results.