I use GH 3 parts nutes, and it's wtritten on the back of the bottle the amount of each part to mix in water. (First the water must be PH balanced before adding the nutes). But the most important is the EC value. I use to put twice they advice, but my EC is correct and the plants don't burn. I put more like 321 in the veg state, and 123 in the bloom state ( for 1 liter and not for 2 liters) but the EC still rises from seedlings to flower except the last flush.