California Wastewater Treatment Operator Practice Exam 2025 - Free Wastewater Treatment Operator Practice Questions and Study Guide

Removing carbon dioxide from a pond results in an increase in pH levels. Carbon dioxide in water typically forms carbonic acid, which contributes to the acidity of the water. When carbon dioxide is removed, there is a reduction in the amount of carbonic acid available, leading to a more alkaline (higher pH) environment.

This change in pH can significantly affect the aquatic ecosystem; for example, higher pH values can influence the solubility of certain nutrients and gases. Additionally, it can impact the health of aquatic organisms, including fish and invertebrates, which have specific pH tolerances.

The other scenarios do not correctly align with the effects of carbon dioxide removal. While promoting aerobic conditions can occur due to increased oxygen availability in some cases, it is not a direct result of removing carbon dioxide. Algal blooms can occur for different reasons, such as nutrient surpluses, NOT specifically from CO2 removal. The decrease in pH would occur if carbon dioxide were to accumulate rather than be removed, moving the balance towards more acidic conditions.