There are always bio-products to such reactions.

If the smell didn't kill you, sure :razz:

And if urine and feces were invisibly merged with this oxygen, then that's good too, right? Water changes are the easiest and simplest form of keeping water quality up. Why would you be that lazy?

Well, i was just adressing the "air" aspect of his analogy. As for bioload, that can be neutralized by other biological/chemical reations. I am not advocating not doing water changes but I beg the question, when waste is negligible and bological processes in the aquarium or efficient, is it acceptable to be lazy on the water changes? Is this a old -he said she said- "requirement" that has been passed around aquarists and ingrained into their heads as "rules"?

Sure, I think the less load you have, the longer you can walk that line. But why? Changing water is simple. It's good for the fish. It's good for the corals. It's good all round. So why do we not want to change water?
I maintain it's lazy/cheap. And if so, then this is the wrong hobby.

How is bio-load neutralized? There are always bio-products and elements needed for every reaction. For example and in simple terms raw organics eventually turn to nitrates and phosphates, how are these removed? Chemical filtration removes many trace elements and refugiums will also use up elements such as iron and iodine. These have to be replaced but for the average hobbyist they are virtually impossible to test for accurately. You also have to think long term, perhaps a tank will do fine for a long period of time as the elements slowly deplete as livestock adapts and it can handle a certain amount of stress unfazed but then levels fall below critical and things start to go wrong. Clueless on what exactly is issue is you begin bringing up levels but doing so too quickly results in even more stress perhaps even enough for some livestock to call it quits and dramatic changes in chemistry can cause all sorts of problems like algae outbreaks.

Can it be done, sure but I think it takes more experience than most of us have in order to avoid screwing yourself in the long run. There's no doubt I could stop water changes for months without issue but eventually things will probably go bad and then going back could make things worse. Dosing would help but if you can't test for it knowing exactly what's needed is next to impossible. Constant water changes insures stability overall and IMO is key to long term success.

If all of my perameters are good, how is it more benifical to do frequent water changes. I know it is 'good', but how is it benificial? I am talking about diminished returns here.

Cheapness/laziness might just mean "to do what is required and only required"?

What parameters, how you read the ingredients in synthetic salt mix before?

Well put. I might add however, that we can know EXACLTY what our water is putting into the aquarium so logically, we can adjust for it.

Chemical/biological/mechanical filtration.

Water changes replenish all the elements used by the system. The salt has dozens of components, and you only replace Ca and CaO3, maybe Mg. What about the rest? It's there for a reason. Reefs need strontium, potassium, etc. you don't replace those. While minimal, they're essential (they wouldn't just add it for fun). It also dilutes the DOCs (dissolved organic compounds) that affect the life in the tank.

Again, my question is why not do a water change?

I can't say i have ever read it, no