randybishop
Well-Known Member
What is a PPM meter for?
And is it the same as TDS?
And is it the same as TDS?
What is a PPM meter for?
- Thread starter randybishop
- Start date
SxIstew
Well-Known Member
PPM testers actually measure in EC and convert to PPM. Unfortunately the two scales (EC and PPM) are not directly related. Each nutrient or salt gives a different electronic discharge reading. To overcome this obstacle, an arbitrary standard was implemented which assumes “a specific EC means equates to a specific amount of nutrient solution”. Consequently, the PPM reading is not precise at all, it is only an approximation, a ball park figure!
It gets worse! Nutrient tester manufacturers use different standards to convert from CF to the PPM reading.
1. Hanna 1 MS/CM = 500 PPM
2. Eutech 1 MS/CM = 640 PPM
3. New Zealand Hydro. 1 MS/CM = 700 PPM
TDS stands for Total Dissolved Solids. This is just one of the ways to arrive at EC, Electrical Conductivity. EC is the most consistent measure of gross nutrient solution strength.
It gets worse! Nutrient tester manufacturers use different standards to convert from CF to the PPM reading.
1. Hanna 1 MS/CM = 500 PPM
2. Eutech 1 MS/CM = 640 PPM
3. New Zealand Hydro. 1 MS/CM = 700 PPM
TDS stands for Total Dissolved Solids. This is just one of the ways to arrive at EC, Electrical Conductivity. EC is the most consistent measure of gross nutrient solution strength.
quisqueyano
Well-Known Member
This link probably explains everything you want to know: http://www.getbluelab.com/Support/Understanding+what+ppm+scale+to+use.html
"CF and EC are measures of electrically charged nutrient ions in a solution. Pure water will not conduct electricity. Water usually conducts electricity because it is full of impurities, in our case, electrically charged nutrient ions. The two black dots on the end of Bluelab nutrient probes are called electrodes. When these are placed in a solution, an electrical current passes from one electrode, through the water to the other electrode and counts the number of electrically charged ions present. This represents the units measured - CF or EC.
ppm measures parts per million. ppm is known as dimensionless quantities; that is, they are pure numbers with no associated units of measurement. A mass concentration of 2mg/kg - 2 parts per million - 2ppm - 2 x 10[SUP]-6[/SUP]."
And yes.
"CF and EC are measures of electrically charged nutrient ions in a solution. Pure water will not conduct electricity. Water usually conducts electricity because it is full of impurities, in our case, electrically charged nutrient ions. The two black dots on the end of Bluelab nutrient probes are called electrodes. When these are placed in a solution, an electrical current passes from one electrode, through the water to the other electrode and counts the number of electrically charged ions present. This represents the units measured - CF or EC.
ppm measures parts per million. ppm is known as dimensionless quantities; that is, they are pure numbers with no associated units of measurement. A mass concentration of 2mg/kg - 2 parts per million - 2ppm - 2 x 10[SUP]-6[/SUP]."
And yes.
randybishop
Well-Known Member
Thank you for that information, it's confusing!
So is a PPM meter needed in a DWC setup?
So is a PPM meter needed in a DWC setup?
DriftWaffle
Member
Makes life a helluva lot easier for sure
I run nutradip trimeters in almost every res or controller I use to know where everything is at any given moment.. no guesswork.. I highly recommend them
Malevolence
New Member
Yea you need some way to measure you nutes... ppm meter, tds, ec whatever... they are all fine as long as they can measure 'how much' of something.