Calculating PPM

[xrob415x]

Hey guys I have a question. Say I need 300 ppm of calcium and I am using a additive that is 2% calcium what calculation would I use to figure this out. How can you figure out the individual ppm of an element in a solution?

 

[420Gator]

you would need 15000 ppm of said product to get 300 ppm of calcium and that would surely kill the plants... why would u need 300ppm of calcium????

edit* it might not add up to a number that high but if theres other stuff in there youd most likely go to high trying to hit 300. its probly only 2% because u dont need much

 

[xrob415x]

I dont need 300ppm bro it was just a hypothetical situation lol I was just using that as an example. But what equation did you use to come up with the 1500ppm??

 

[sedate]

you would need 15000 ppm of said product to get 300 ppm of calcium and that would surely kill the plants... why would u need 300ppm of calcium????

edit* it might not add up to a number that high but if theres other stuff in there youd most likely go to high trying to hit 300. its probly only 2% because u dont need much

Um. ^^ This is wrong.

dont need 300ppm bro it was just a hypothetical situation lol I was just using that as an example. But what equation did you use to come up with the 1500ppm??

This is a fairly straight-forward division problem.

2% work out to 20,000ppm. Since - you know - 20,000 is 2% of 1,000,000.

So - you then would need the amount of liquid you plan on making 300 ppm . . .

For simplicity's sake we'll use a 1 gallon hypothetical solvent.

Which is equal to 128 ounces.

So what happens if we apportion a single one of those 20,000 ppm ounces among the other 127 ounces of a hypothetical 1 gallon solute?

I am - of course - assuming miscibility.

20,000 (strength of the solute)/128 (number of times we are dividing it into the gallon) = 156.25

So we would get 156.25 ppm for adding a single ounce of said Calcium solution.

So the rough answer to your question is 2 ounces of calcium solute to 1 gallon of a given solvent, assuming miscibility.

For fun, we could do it in ml and get really precise -

1 gallon = 3785.4 ml
20,000/3785.4 = 5.28
300/5.28 = 56.8 ml - which is just a tick less than 2 ounces - about right since above we'd end up with about 312ppm if we went with the ounce measurement.

 

[JeenYuss]

http://www.manicbotanix.com/calculators/ppm-in-solution-calc.php

Check out that website. has a calculator to figure out everything.

Here is a video of someone showing how it's done. pretty straight forward.

http://www.youtube.com/watch?nomobile=1&v=ZhVuu_kqqEo