Question
Hello, I am chasing problems with growing healthy St. Augustine grass.  Thought I knew the grass till I got on 5 sunny acres, with atleast a slight wind all the time and a suntan index of 15. :)  It's sandy soil, and 575' well with water that a fellow with greenhouses around the corner says is testing at 250 parts per million of Sodium.  He says that's why my turf isn't growing robustly and green.  I have a sprinkler that dumps 8 GPM and it doesn't take long to put an inch of water on in the heat of the day.
Another place online, I see an article that says St. "A" can take alot of salinity, up to 16 mmho's.  Can you help me convert either ppm to mmho's, or vice versa?  I have a sprinkler guy set to put some heads in the ground, and need to make a quick decision on whether to proceed from the deep well.  Grass is suffering random spots of brown tips, but don't receive much rainfall local, and all 90 degree plus days there.  It actually looks even golder/browner after dumping an inch of water on it during the day.  I have to keep the large sprinkler moving to cover all the areas, till I get some irrigation help.  It's not as fast growing and lush green as when I lived in the city, but that shallow well was full of iron, and I had 40% shade.  The look doesn't seem to fit any afflictions that I see online for the St. A.  I'm wondering if it is just plain old dying of thirst.
But I would like to know how ppm relates to mmho's.  Thanks for any advice.

Answer
North Carolina State University website (www.ces.ncsu.edu/depts/hort/greenhouse_veg/resources/tools/ecConverter/ec-converter.html) has one of those conversion meters that turns your ppms to mmhos in the blink of an eye.  Rather than simply doing the math I think you might like to take a look.  

For the sake of time, I am also refering you to another NCSU Floriculture Research post, "Electrical Conductivity: Units and Conversions" (www.ces.ncsu.edu/depts/hort/floriculture/Florex/EC%20Conversion.pdf).  

Finally, I am you understand The Long Island Gardener and I don't know nothin' 'bout fixing flowers in Florida.  When I try, I usually end up wrong.  So I have to be honest, I would love to answer your questions, but I am not sure it would be the right answer - I would be in fact speculating on an answer, and I don't like to do that.  Actually, I love to do that, but I am frequently wrong with my answer - you guys have different fungus problems, different insect pests (and giant spiders), different grass, you even have different water!  If I waited a week or two to put together one of my "maybe" answers, your grass would just up and die.  Can't sleep with that on my conscience.

Write me again when you move to North Carolina.

Or if you have a problem with your Hibiscus or your Gardenias.  I guess you won't be growing any Bluegrass down there.

Good luck with your Saint Augustine lawn and salt water (yet another problem I have not had on Long Island!).