Im confused as to what chelation removes the Mercury from the nervous system i.e. would that be dmsa ect or the ALA. Im getting a bit confused by it all

Dmsa removes body burden mercury,and ala removes brain mercury.
Remember to clear all body burden before working on the brain as the Ala crosses blood brain barrier and can actually carry more mercury from the body into the brain.

If the body is not eliminating some mercury naturally, there is usually gut/liver issues, and too many other things burdening the immune system as well (e.g infections, viruses etc).

Some mercury is naturally eliminated by the body itself, but most of it is bound up tightly and needs chelating. But what happens when someone's system is overwhelmed? I just feel that things get recirculated and the person literally remains poisoned or is repoisoned continually.

I think chelation is necessary but I reckon the person needs to address their gut and liver with appropriate diet and supplements as well, or before chelating at all.

That's just my ten cents worth.

Cilantro is excellent for lower cns mercury mobilization and detox. Always to protect with C, E and Algin when detoxing.