I was just going to let this go, because it might be steering the thread in a direction that it was not intended(?).
I think the stuff that I am experiencing is NOT unused feed or fecal. That stuff will not latch onto pipes, walls, etc... am I correct? I imagine unused feed/fecal material as to mixing/floating around the water or laying on the bottom. The stuff I have is attached. Sure it can break off and then float around, but for the most part it is attached and looks moss like, or hairy. I then assume this is mulm(?). You mention that the feed/fecal material can create a "producing heterotrophic bacteria". Does that stuff attach to objects, particularly attach itself to the good bacteria? Or is it distributed thoughtout all the water?
If I understand this correctly, you can physically see a good bacterial colony much the same as you can see mulm?.... Can you also see biofilm in any way?
