Yeah I am trying to figure out what organics Could be I don't over feed and what does get left normally is gone by my corys. and all the plant matter I clean out. even before it Dies off the plant if i notice it in time. Unless it is in my substrate and it very well could be. Like i said i am new. So cleaning the substrate isn't always easy. And some stuff just wont raise up through my siphon and it's easy to get with by hand eather, whether it be to small to grab by hand or in a place my hands can get to. (behind the driftwood.) i don't move my driftwood as my loaches tend to stay there and i don't want to hurt them moving it around. i mean I understand what your saying. I just Not sure what it can be. If that makes since.