[MrGoodkat]

As the title states, why does Rhizoclonium algae look brown?

I have seen many pictures of it, and I believe I have it in my tank. For the longest time, I thought it was filamentous diatoms (due to the brown color), but I recently realized we have a microscope at work. After looking at it under the microscope, I am all but certain it is Rhizo.

But it looks light brown in my tank and in pictures I have seen. Anyone knows why this is the case? I am not looking for advice for my particular issue, though. I am more curious how it gets its brown color.

 

[Mark Fisher]

Most algae appear green because they have a preponderance of chlorophyll in their cells. Rhizocloinium has other accessory pigments that give it a brown color. Other types of algae can appear red, blue-green, orange, etc., for the same reason, just different photosynthetic pigments.