@brandon429 Sorry I missed your replies earlier.
I think there's a lot that's great in what you are proposing. Some of your suggestions I strongly
disagree with - like that sandbeds have no worthwhile organisms. My sandbed is filled with stuff like these Tanaid shrimp whom I've watched munch patches of sandbed dinos.
If I pull a sample of detritus+sandbed right now, I'd find a ton of copepods and nauplii, some of those tanaids, nematodes, other worms, ciliates, other classes of pods etc.
Where I agree with you is that once a sandbed is covered and dominated in toxic dinos, there is little of value there. It is essentially as you say, "just dirt" (at best). Toxic dinos exclude healthy diversity from their domain.
This thread is still in large part experimentation, and a deep detritus clean ought to be one path that gets experimented with. [Another prong of an approach that I need to write up into the OP is using a controlled onslaught of grunge-eating bacteria - a la the BRS document on Dr. Tims waste-away.]
I am increasingly convinced that there's a connection between sandbed dinos and the sand/debris/bacteria community that is strong and can shape the fate of the dino population.
I don't think the same connection holds for the stringy dino types. They obviously have different nutrient strategies. One is inseparable from the sand and the other seeks out the highest flow and forms strings where nothing else can touch it. For the stringy high-flow types, though a sand-rip might provide some benefits, it seems pretty unnecessary since there are many other ways to target the dinos more directly and controlling the water chemistry is often enough to control them.
I'm going to stop rambling, but sandbed dinos don't just
happen to occur on the sandbed. It's their place, their meal ticket, and their way of life. A sand rip would disrupt all of that and detritus removal could be viewed as a proxy war over bacteria communities. We can't quantify bacteria but we can quantify the gunk we rip out of a sandbed. It certainly feels like one way that ought to be explored as we try to get a handle on what these guys are doing down there.