That's the beauty of Hempys, you can make it as easy or difficult as you want. Somebody coming from a hydro background is usually amazed at the simplicty and somebody from a soil background, is usually amazed at the effectiveness.
My personal formula for a watering/feeding regimen is 8ml of FNB, 5ml of cal-mag and pH'ed to about 5.8-6.0. I started out measuring pH every time I mixed up a solution. Then I figured out that my tap water is pretty consistent. My pH pen just doesn't get used anymore!
After transplanting, I water about a cup or two (1/2 liter or so) every day for 2 or 3 days. Then about a quart/liter each day until the roots hit the res (about a week). After that, the plant takes off and I feed about two quarts/liters every three or four days until harvest/flush. Full strength start to finish!
There is more than one way to skin a cat and this is just one way, but, when I went looking for easy, simple, and uncomplicated, I found it in abundance!
Also, I believe the fourth number refers to the Mg ratio.
Namaste
I'm also watering about 500mL per day right now because I have just transplanted into hempy.
My question is your measuring. I am using FNB as well and was calculating full strength at 8mL/gallon but only using 500mL-1000mL per watering I was wondering how you measured. Do you do 2.5 per 1000mL or do you measure your nutes a different way?
Thanks