So, if I want to add 1ppm to 40liters(10gallons) I do this math..

1.429/100=.01429

.01429*40=.57g

my stock solution of CSM+B is 14.7g in 500ml. So....

14.7/500=.294 (grams of CSM+B per ml of solution)

.57g/.294= 1.9

S0, 1.9ml of the solution would give me 1.0mg/l

Fe in 40liter aquarium

Fertilator says I currently add 5.2mg/l Fe, so...

1.9*5.2=9.88ml of my CSM+B stock solution to equal the Fe in Flourish/Fl. Fe

Of course, all this math makes me realize I seem to be adding alot of Fe to this tank. Remember this is 3x week so I am adding 15.6mg/l Fe weekly to this tank! I slowly built my dosing up starting at 1ml Flourish 3x week and over about 2 months I upped it to where I am now. The plants are growing nicely and I did notice a difference between 1ml and 2ml, all other params. stayed the same when I was doing this.

Anyway, sorry if I seems so math illiterate and thanks for checking over my calculations

Maybe this will help someone else also.