I use the drop test for everything except calcium and magnesium.
There are highly accurate electronic devices that can test just about all the chemicals and you could easily spend a grand on them. (Foster and Smith sells them). Has anyone compared the the dropper tests with more, scientifically accurate devices?
There are highly accurate electronic devices that can test just about all the chemicals and you could easily spend a grand on them. (Foster and Smith sells them). Has anyone compared the the dropper tests with more, scientifically accurate devices?