Yeah massively, overfert will be your biggest problem being still new to this game
I would say you need it. But different people have different opinions.
If you follow the advice here I think you should be ok
Get a bottle of grow ! Its important !
Only feed a hungry plant, never feed something that isnt hungry.
Don't chase a million different deficiencies if you are using a balanced food its either too much or too little thats it.
Veg - Do not feed IMO but it is dependent on the size of the plant, if I am in a 10-20 litre pot of good soil I don't feed for the entire of veg (sometimes up to 3 weeks). I would not go over 3 ml if my plants did need feeding during this period. I do however feed additives for root growth, and beneficial fungi and bacteria.
First week of flower maybe start the plant on 1ml of grow ( they don't need flowering food til they have basic flowers) up this to a maximum of 3ml ish over the next couple of weeks and then drop it down to 1ml of grow and 1ml of bloom on your third week of flower you might want to up the bloom to 2-3 ml (keeping the 1ml of grow).
Around this time (week three) you may get a mag def using just grow and bloom, treat with epsom salts (magnesium sulphate) and that will be the last you see of mag def
Keep upping the food to a max of 4ml over the next few weeks but only up it when its hungry. A large plant (1 - 1.5 metres, multiple heads) with heavy bud growth will happily munch its way through 4ml of bloom and 1 ml of grow. A smaller plant will drown and die in an unpleasant overdose of food. Bear this in mind.
Towards the last couple of weeks drop the 1ml of grow (this is IMO I think it tastes better with less N towards the end and it also helps to bring out the colours).
Last week before flush pure bloom food, possibly drop the dosage to 3ml (maybe up it, its all down to the plant).
Final week pure water for a week
If you over do the nutrients at any point it will be fucking nightmare, just always keep them hungry. They grow faster like that as well
I hope this helps and do not hesitate to ask any questions.
Also check my journal out its in my sig
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