Not sure what I've seen here (notice the small grey patches in the water on the upper right half of the photos?). I suppose it's some kind of AS/water column interaction. I've observed it in rare cases over the course of some years.
Sorry for the bad pictures but as you can imagine the clouding happens quickly and disappeares fast in the current. Grabbed the camera and shot away without any fiddeling.
And no it's not a shrimp digging in AS which might have caused it and which could have looked similar. There was too much clouding and too much ground cover for shrimps to reach the substrate.
Congregations of bacteria is another idea which came to mind.
Best regards,
Detlef
Sorry for the bad pictures but as you can imagine the clouding happens quickly and disappeares fast in the current. Grabbed the camera and shot away without any fiddeling.
And no it's not a shrimp digging in AS which might have caused it and which could have looked similar. There was too much clouding and too much ground cover for shrimps to reach the substrate.
Congregations of bacteria is another idea which came to mind.
Best regards,
Detlef