Dear 王嘉麟 Wangjialin

I hope this message finds you 王嘉麟 Wangjialin well! I wanted to dive into the topic of Spirulina culture in open ponds, particularly concerning the potential for contamination. Given the use of Zarrouk medium, it seems like a prime candidate for various algae species to invade, especially since outdoor settings can introduce airborne or waterborne spores.

From my observations, the most common contaminants we might encounter include Chlorella sp., which is often green and round-shaped, making it a frequent visitor in outdoor cultures. Then there’s Scenedesmus sp., which tends to form small colonies with distinctive spines, and Ankistrodesmus sp., known for its elongated or crescent shapes. Lastly, we should keep an eye out for Anabaena or other filamentous cyanobacteria, as they can be particularly harmful due to their toxin production.

Identifying these species can be tricky without a closer look at their morphology, especially under magnification. If you notice any distinctive shapes—like round cells for Chlorella or spined clusters for Scenedesmus—those could help us narrow it down. For more precise identification, consulting an algal identification key or considering molecular marker analysis might be worthwhile if we have access to those resources.

Looking forward to hearing your thoughts on this!

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(PDF) Algae Strain Identification for Wastewater Treatment

Using Microalgae for Treating Wastewater | Request PDF