When I first went carnivore I was salting my meat and drinking water mixed with various salts and supplementing magnesium.

I would get light-headed/dizzy when standing too quickly.

After a while I stopped all the salt (don't even add it to meat any more) and now I don't get light-headed any longer.

I do sometimes drink mineral water, mostly because I enjoy the bubbles in carbonated water. Mostly I drink very pure water (fluoride removed).