High Spanyxi,
You should use a EC meter! This schedule is not specially for cannabis.
With a EC meter you can give EC 1.0 the first week and after you can up this with + EC 0.1 every week till you reached EC 1.8 (do not give more then EC 1.8).
Give water with pH 5.7 and the above called EC with 1.8 till 1 week before harvest when you start to flush and only give plain pH 5.7 water.
When you do not want to use a EC meter then give only half of what they advice on the nutrients bottle. This is more then enough for cannabis!
Give water with 20% drain to flush out the build up nutrients and salts every time you water!
Happy Growing! 😋