Which type of algae is commonly found in improperly maintained swimming pools?

The primary type of algae commonly associated with improperly maintained swimming pools is green algae. This type of algae thrives in conditions where water chemistry is not adequately balanced, particularly in environments with high levels of sunlight and stagnant water. Green algae can grow rapidly, forming a greenish layer on pool walls and surfaces, making the water appear murky and uninviting.

While white algae does exist and can occur in pools, it is less commonly referenced compared to green algae. Purple algae, often characterized by its reddish hue, tends to be more associated with marine environments and is not typically a common issue in swimming pools. Therefore, the focus on green algae as the predominant issue in improperly maintained pools makes it the correct answer.