Yes, sometimes I wonder what may come along in the future that will change the quality of feedback and knowledge of how to test and control these processes even better. When I first started thinking about tank water in the early 1960's the books I read gave glimpses of what aquarists had thought in the period of 1920's through 1950's. In hindsight, plenty of what was thought to be true was misguided, looked at with today's information. From the 50's through 1980 the understandings became better and more widespread but with the advent of usenet and the fishless cycling idea around 1980 the quality and distribution of basic cycle information really began to take off. I'm sure the day will come when our current understandings look antiquated. Perhaps recent developments in nano-etched surfaces and sensors will reduce the cost of measuring a lot more substances and someone will combine that with more knowlege of what substances are making differences in the biofilm lifecycles of our species of interest.
I sometimes wonder whether our processes are fairly predictable for the standard major cannister filters (Eheims, Renas, Tetratecs and Fluvals) and the Aquaclear HOBs and some of the chunkier Fluval internals but whether there are perhaps more problems with our model when you get into filters that have a lot less biomedia like those with little "screens" of material on plastic frames or little bags that can only hold a few rings of material. Obviously the basic principles still hold up for most of these as we have evidence from members of most of them working eventually but I still can't help wondering sometimes whether there are some variations in filter design that could be giving more trouble during the cycling process than we realize, due to things we don't understand.
Really though, the greatest variations do probably lie completely unnoticed by us in something we have no idea of like certain trace element levels or certain organic molecules or unknown wars going on between different bacterial species. I mean, it could be that Nitrosomonas don't like chromium above 0.002ppm or some weird thing like that, just to make something up! It could be that some Nitrobacter or some other weird species gets in there and competes for space and wins sometimes and we have to wait for it to die off and give up its media positions and we have no idea this is why we're waiting so long. Living systems are so very much more complicated than chemistry would be.
~~waterdrop~~
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