Well, if you change things based on information, it ought to be good information, not like WMD's in Iraq(they never did exist now did they? Nukes? Nope)
Same type of deal here, there might not be any NO3 at all, there might be 40ppm, you do not know.
If there is 40ppm, is that "Bad"?
Not that I can tell, but many run around on the web claiming it is............
but offer no proof or evidence that it really is.
Check that out first before you do ANYTHING based on a test kit reading.
Many hold the test kit and testing up like some religious text or icon.
They do not understand it one bit yet believe in it and want to do the right thing.
The intent is good, but the assumption is not.
I question the assumptions, many assume I'm questioning their intent. Sometimes I am

hehe
Regards,
Tom Barr