About two weeks ago I collected several MetaRocks from an Eliminite system that has been in operation for about seven years. I have been meaning to take a bio-film sample from the surface and look at it under a microscope but have been busy and I forgot about the sample.
Today I got tired of doing what I have been doing and remembered the cup with MetaRocks sitting on my desk. The video shows the biological activity in the tiny scrape I took from the surface of the MetaRocks.
I think it is important to note that, after two weeks of sitting on my desk in a cup, the microorganisms are still alive and active. This fact illustrates one reason why eliminite fixed-film systems are so robust and reliable. The microorganisms stay alive, imbededded in the film, even though they are not receiving influent.