Just a update on this thread as I need some last advice please, as yesterday I purchased some K2SO4, so am now working out how much I will be needing to add to my 500ml solutuion at 18ml a dose 3x a week. The K2SO4 will be added to my Macro Solution. Sorry if this turns into a confusing/complicated essay but you can skip it all if you read my main question below and just answer that for me
( I also am not dosing KNO3 as you know but have used it below just for examples)
Anyway my MAIN question, on
http://calc.petalphile.com/ do I need to follow the grams for EI Daily or The Estimative Index, I have seen this question asked by some people on here and no one replied to them so am I right in saying EI daily would be you add KNO3 each day at the grams it provides "18ml a day in my scenario", and the The Estimative Index provides the grams for 2-4x week which I will be doing 3x 18ml. I know me and Zorfox spoke about it, and I think we talked about EI daily but I am getting massive gram differences between the two which in is putting me out of the PPM ranges, a good example is MGSO4.
Here is an example of what I mean:
My Measurements recommended from where I purchased and what I'm dosing now minus the KNO3
KNO3 - 4tsp = 29grams = 7.11ppm per dose, (21.33ppm week)
KH2PO4 - 1sp = 9grams = 2.51ppm per dose = (7.53ppm week) Way To Much?
MGSO4.7H2O - 6tsp = 31grams = 1.22ppm per dose (3.66ppm week) Way To Low?
The Estimative Index From Calculator Below:
KNO3 Nitrate 30g 7.50ppm each dose (22.5ppm week)
KH2PO4 Potassium Phosphate 4.6g 1.30ppm each dose (3.9ppm week)
MGSO4.7H20 Magnesium Sulphate 126g 5ppm each dose (15ppm week)
EI Daily From Calculator Below:
KNO3 Nitrate 13.044g 3.20ppm each dose (9.6ppm week)
KH2PO4 Potassium Phosphate 2.1g 0.60ppm each dose (1.8ppm week)
MGSO4.7H20 Magnesium Sulphate 50g 2ppm each dose (6ppm week)
So EI daily would hardly get me in the ppm ranges at 3x a week, and The Estimative Index would get me in the ranges from the first dose, and keep me in the ranges roughly all week.
For some reason my starter kit has low MGSO4 even compared to EI daily, and MGSO4.7H2O The Estimative Index recommends 126g, I am only using 31g, so this what I mean by its quite scary for someone who is inexperienced, and I know I am making this more complicated, way more complicated, but do I go with EI daily or The Estimative Index.
If my Macro mix sounded right I could of just added 1/4 tsp K2SO4 to my tank 3x a week but I want my macro's all together in a solution, I guess this is why its become a little complicated and the way I have presented all this.
Also to try and answer my own question about the K2SO4, plantbrain recommended K2SO4 at 1/4tsp 3x a week, that's 7.98ppm a dose, (23ppm week) and my 18ml would be 41g into 500ml, 18ml 3x a week gives me 22.5ppm. So all in all am I right in saying The Estimative Index is correct for 3x a week.
PPM Ranges:
KNO3 - 5ppm-33ppm
KH2PO4 - 1-3ppm
MGSO4 - 5-11ppm
K2SO4 - 9-33ppm
My Tank
90 litres - 20G
Think there correct from the "Yet Another Nutrient Calculator"
Also thanks jfynyson thanks for your input, I only really needed to know the estimated teaspoon weight just to see how much grams I was dosing so
http://calc.petalphile.com/ could tell my ppm each dose, the link zorfox provided is quite close with teaspoon weights but as I learned on my scales each teaspoon can fluctuate a gram or two or my scales are busted lol.