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[happyconcacti]

Hi All,

Calculating PPM, an example:

Say you want a 750 PPM concentration of GA3. You want 100mL (0.1L) solution to soak your seeds in.

1L water = 1000g = 1,000,000mg
0.75g GA3 = 750mg GA3

750mg/1,000,000mg = 750PPM

So for a concentration of 750PPM you would add 0.750g of GA3 to 1L of water.

Well, this is a lot of GA3 solution, cacti seeds are small. So now you only want 0.1L (100mL) of solution.

So you multiply the number of grams of GA3 by 0.1.

Therefore, for 100mL of solution, you would add 0.075g (75mg) of GA3 to 100mL water.


HCC

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[Roze]

I use this method :

100mg of acid dissolved in:

25 ppm   = 4000 ml of water
50 ppm    = 2000 ml of water
100 ppm  = 1000 ml of water
250 ppm   = 400 ml of water
500 ppm   = 200 ml of water
1000 ppm  = 100 ml of water

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[nobody]

That only works when the chem used is at 100% purity. For example, 90% pure GA3 requires 110mg dissolved in 100ml H2O for a 1000 ppm solution. This does not matter too much on small volume solutions but it would make a large difference if you are using one gram or more.

 

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[happyconcacti]

Hmmmm,

So I just mixed 62mg of 90% GA3 into 79mL water.

What's the actual PPM that I ended up with?

(62mg * 0.9)/ 79mL  = about 700 PPM

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