MrStickyScissors
Well-Known Member
I just bought a blue lab meter. How do i do the math to convert ec to ppm?
ec or ppm
- Thread starter MrStickyScissors
- Start date
hondagrower420
Well-Known Member
You put the lime in the coconut.
You don't go from ec to ppm.
Only ppm to ec.
You don't go from ec to ppm.
Only ppm to ec.
MrStickyScissors
Well-Known Member
Anyone else haha
hondagrower420
Well-Known Member
hondagrower420
Well-Known Member
Ok so say your meter reads 1.0ec
That could be
500ppm
640ppm
700ppm
You cannot go from ec to ppm.
And next time someone takes time to answer your question, how about a thank you.
That could be
500ppm
640ppm
700ppm
You cannot go from ec to ppm.
And next time someone takes time to answer your question, how about a thank you.
hondagrower420
Well-Known Member
What are you really asking?
What are you trying to accomplish?
What are you trying to accomplish?
MrStickyScissors
Well-Known Member
my meter is a blue lab. It reads at 700ppm setting and 500ppm setting or ec setting. I just want to know how to work it. Oh and think you twice
hondagrower420
Well-Known Member
TDS defined
TDS stand for total dissolved solids and refers to the measure of all substances contained in a liquid. It is the measurement used to determine nutrient strength. TDS in hydroponics has two different readings; Conductivity and Parts per Million (PPM). Conductivity is the more scientific of the two readings, it can be represented as Electro-Conductivity (EC), Conductivity Factor (CF) or Micro Siemens per square centimeter (MS/cm). PPM is not quite as accurate a representation of TDS but much more common within the United States. If you talk with a gardening friend or read information on a forum chances are the growers there will talk in PPM terms and not Conductivity.
PPM is directly calculated from Conductivity and there are two different scales: NaCl (1EC = 500ppm) and the 442 scale (1EC = 700ppm). Different meters offer different conversion factors and some offer a sliding scale or the option to change the scale to your choosing.
Testing your TDS
There are not many manual testing options for TDS and the ones we have seen use to large of a value range to be useful for hydroponics. Digital Meters are you best option for monitoring your nutrient strength.
All TDS meters are, in reality, conductivity meters, the PPM meter still measure conductivity but use a conversion formula to translate its reading to ppm. TDS meters work by applying a voltage between two or more electrodes. Positively charged ions will move toward the negatively charged electrode, and negatively charged ions will move toward the positively charged electrode. Because these ions are charged and moving, they constitute an electrical current. The meter then monitors how much current is passing between the electrodes as a gauge of how many ions are in solution.
TDS meters will only detect mobile charged ions. They will not detect any neutral (uncharged) compounds. Such compounds include sugar, alcohol, many organics (including many pesticides and their residues), and unionized forms of silica, ammonia, and carbon dioxide. These meters also do not detect macroscopic particulates, as those are too large to move in the electric fields applied. Bacteria and viruses also won’t be detected.
TDS stand for total dissolved solids and refers to the measure of all substances contained in a liquid. It is the measurement used to determine nutrient strength. TDS in hydroponics has two different readings; Conductivity and Parts per Million (PPM). Conductivity is the more scientific of the two readings, it can be represented as Electro-Conductivity (EC), Conductivity Factor (CF) or Micro Siemens per square centimeter (MS/cm). PPM is not quite as accurate a representation of TDS but much more common within the United States. If you talk with a gardening friend or read information on a forum chances are the growers there will talk in PPM terms and not Conductivity.
PPM is directly calculated from Conductivity and there are two different scales: NaCl (1EC = 500ppm) and the 442 scale (1EC = 700ppm). Different meters offer different conversion factors and some offer a sliding scale or the option to change the scale to your choosing.
Testing your TDS
There are not many manual testing options for TDS and the ones we have seen use to large of a value range to be useful for hydroponics. Digital Meters are you best option for monitoring your nutrient strength.
All TDS meters are, in reality, conductivity meters, the PPM meter still measure conductivity but use a conversion formula to translate its reading to ppm. TDS meters work by applying a voltage between two or more electrodes. Positively charged ions will move toward the negatively charged electrode, and negatively charged ions will move toward the positively charged electrode. Because these ions are charged and moving, they constitute an electrical current. The meter then monitors how much current is passing between the electrodes as a gauge of how many ions are in solution.
TDS meters will only detect mobile charged ions. They will not detect any neutral (uncharged) compounds. Such compounds include sugar, alcohol, many organics (including many pesticides and their residues), and unionized forms of silica, ammonia, and carbon dioxide. These meters also do not detect macroscopic particulates, as those are too large to move in the electric fields applied. Bacteria and viruses also won’t be detected.
To get the .7 scale ppm just do ec x 700
To get the .5 scale ppm just do ec x 500
1.0 ec x 700 = 700 ppm on the .7 scale
1.0 ec x 500 = 500 ppm on the .5 scale
Yes you can
hondagrower420
Well-Known Member
No you can't.
hondagrower420
Well-Known Member
I mean I know the math, duh.
But what is the point? Why would anyone need to do this?
There is a reason why ppm uses a conversion factor. And ec doesn't. Ec doesn't get converted.
But what is the point? Why would anyone need to do this?
There is a reason why ppm uses a conversion factor. And ec doesn't. Ec doesn't get converted.
Umm ok
hondagrower420
Well-Known Member
Umm ok.
Get the fuck out of here with your bad info.
I said it once, I guess I have to say it again.
There is no conversion factor used to calculate tds using an ec meter
There is a conversion factor used with calculating tds using ppm meter.
Math doesn't lie. Keep it moving ricer
hondagrower420
Well-Known Member
Ok. I'm not argueing the math.
EC is a constant. Doesn't change
Ppm is a variable that expresses a conversion from ec
The only reason to use this is if your nutes giving you a target ppm and you have a ec meter. Even then you don't have the conversation factor that your nute company uses so you are guessing.so you would have to guess.
Ppm meters do the conversion for you. No guess work.
hondagrower420
Well-Known Member
Resinhound
Well-Known Member
I dont see the point in this.Just using ec as a reference seems like the best option,if its available. Universal language.
GrowerGoneWild
Well-Known Member
I just use PPM, it seems more common. however the conversion factor. A GH feeding chart uses PPM for example.
Ec is more universal, no conversion. However its for conductivity,. My buddy uses this over PPM.
As long as my measurements are consistent, and I can reproduce the result. Its not a problem as long as I stay with the same scale. Whats most important is reading your plants and the correlation of that number to plant health.
Ec is more universal, no conversion. However its for conductivity,. My buddy uses this over PPM.
As long as my measurements are consistent, and I can reproduce the result. Its not a problem as long as I stay with the same scale. Whats most important is reading your plants and the correlation of that number to plant health.
hotrodharley
Well-Known Member
The disparity is only between brands. EC is more accurate in determining feed and PPM is simply derived from EC. All units measure the EC and then convert for your convenience or whatever. Many who are incapable of working with this without some deeper understanding should perhaps stick to mixing nutes at reduced levels always. If not they are on here "Help my babies are all fucked up!"