Well water, like any water that is not enclosed and constantly in motion, can develop algae. Knowing what algae may potentially grow in your well, and how it might affect you and your drinking water, can help you decide whether you should look into treating or filtering your drinking water.

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Well water can sometimes be contaminated by algae.

Toxic Blue-Green Algae

Like other forms of algae, blue-green algae forms in still water, especially when the water temperature is warm. Some types of blue-green algae, like cyanobacteria, release toxins which can cause liver and nervous system issues. Since blue-green algae does not often give water a different taste or smell, the easiest way to identify blue-green algae is by an odd coloration or thickness in your water.

Nutritious Blue-Green Algae

Other types of blue-green algae, like Spirulina, have high amounts of nutrients and can be beneficial to your health. However, blue-green algae that are recommended as vitamin supplements are always filtered and purified.

Green Algae

Green algae are another common type of algae that can be found in drinking water supplies. This algae generally does not cause health problems, but it can give your water a distinct green color.