I understand that EI is adding more than enough ferts so that the plants are never without.
And i know that if i follow the suggested routines laid out by TOM that i can't go far wrong.
And i know its not an exact science.
Here is the BUT
If the MAX Weekly uptakes are as follows:
Tom suggests that you dose as follows for a 10-20 Gallon Tank
+/- 1/8 tsp KNO3 (N) 3x a week
+/- 1/32 tsp KH2PO4 (P) 3x a week
+/- 1/4 tsp GH booster once a week(water change only)
+/- 1/32 tsp (2ml) Trace Elements 3x a week
50% weekly water change
So lets take the 1/8 tsp KNO3 added to a 10 Gallon
tank that will add 12.15ppm of NO3 3x week.
Now if you add 1/8 tsp KNO3 to a 20 Gallon
tank you would only be adding 6.07ppm NO3 3xweek.
As you can see it is recommended that the larger tank should require a leaner dose than the smaller one.
So thats why i wanted the ppm's as this can be expressed to any size tank.
I also noticed that TOM suggested a EI solution mix for a 20 Gallon tank as follows:
25g GH Booster
mix to 1000 DI water and add 5ml daily
this would give a weekly NO3 of 17.01ppm thats less than recommended when dry dosing.
So as its not an exact science,
Should we just aim to exceed the Max daily uptakes therefore looking for weekly ppm's in the region of:
to be added either by making solutions or dry dosing:
PO4 11ppm (high due to the need of the k in the KH2PO4)