Math Problem - help with po4x4

[JohnnyTabasco]

Hey any one really good at math?

250ml po4x4 will remove 3ppm po4 from 4000 liter.

I have 0.8 ppm in 100 liter.

How much po4x4 must I use to get it to 0.3 ppm ?

 

[mcarroll]

I wish I was better at math and I could just tell you the anwer....but instead, I have to say not to agonize so much over .5 ppm of PO4. ;)

(aka BUMP!)

 

[Birddog]

I calculate 1.04 ml.... I'll be interested to see if I'm correct (pretty sure I am). I think this might be a little drastic making this change abruptly dependent upon livestock in the tank

 

[Waterjockey]

I get the same, 1.04. If dosing carbon was really that accurate :)