Hi folks,

I'm from Holland and found this very interesting stuff (EI) and am very curious to try. I'm deeply curious about the results as I'm always fighing the Algae...

I am experimenting for 3 years now with KNO3, KH2PO4 and magnesium supplements.

But on thing I don't follow in the calculations:
desired PO4 level 1-3 ppm

In my test tank of 122 liters net I should (reading the EI work, see below) add 1.1 grams of KH2PO4 per week.

" ====>
20-40 Gallon Aquariums
+/- ¼ tsp KN03 3x a week
+/- 1/16 tsp KH2P04 3x a week
+/- 1/16 tsp K2S04 3x a week
+/- 1/16 tsp (5ml) Trace Elements 3x a week
50% weekly water change
<===="

(1/16 tsp * 6 gr per tsp * 3 a week = 1,125 grams)

But if I add those 1100 milligrams to 122 liters I'm building up 9 milligram per liter (mg/l). Almost 70% of the molecule weight exists of PO4, meaning that I will end up dosing 6,3 mg/l of PO4. That is ten times more that I usual have!!! I thought mg/l is the same as ppm, a word we don't use over here as we use metrics. The online calculations of Chuck are confirming my findings.

Can anyone explain this to me? Am I overlooking something?

Thank you in advance,


Koen van Vliet

PS are there any calculations for dosing Fe / iron?