Depends. I certainly do far less changing of water on my low tech shrimp breeding tank. But that system is minimal fuss and low bioload so anymore is kind of moot. I change water for the opposite outcome to the killing of shrimp, it easily adds calcium and mangnesium to the water due to the tap water qualities where I live. Helps the shrimp with shedding.
The ten high tech systems I help maintain receive up to 90% water change a week. If maintenance is being performed throughout the week then this may happen more than once a week.
Point is the amount is arbitrary. We do clean our high tech tanks, amongst other things, the water change helps prevent the circumstance you outlined before:
The other end of the scale is what
@dw1305 outlined:
Another way of creating a relatively stable environment with a means to support life. Different methods for dealing with a range of setups; low energy to high energy. An explanation of the qualities of zones of REDOX would be far better served by someone with more knowledge on the matter.
Not quite understanding the question. I haven’t seen the OP’s tank so there isn’t really a comparison or judgement I can make here. As for what I do, the sanded area is literally on the bottom glass of the tank and a few mm’s depth. A lot of detritus falls into this area and makes removing it easier (if that’s what you want to do and if it’s necessary).