First time looking for some advice

Hello everyone, this is my first time growing im just looking for some advice on npk at specific times of growth
I have a Northern lights autoflower which is approaching the end of week 4 as well as a liberty haze(photoperiod)
I am using a 400watt Duel spectrum HPS lamp on a 18/6 schedule.
The nutrients i am using are the flora trio and also have a plant magic magne-cal+ for deficiencies
I am growing in a 70/30 coco/perlite mix.
The temperatures and humidity are controlled so they are always 65% and between 20-25 lights on/ off
I have just gotten the plants out of a nute lock it seems the coco they were in had already loads of pre dissolved salts. I flushed them through until their EC matched the input feed i was flushing with which was 0.3 EC.
I think im looking too deeply into this but im getting confused. I have only been feeding a 0.3 EC feed since the flush because im scared they will lock up again.
I have noticed that Northern lights has started popping pistols, im no expert but from what i think is this her preflower stage? Others say Autos dont have pre flower stages.
At the moment i am feeding 1.5ml grow, 1ml micro and 1 ml bloom. It is my goal over the next 2 weeks (transition/early flower) to change this order so that there is more bloom than grow. i am aiming to do a 1,2,3 ratio.
My confusion comes from EC am i doing my feed too weak? or should i start increasing the ec slowly ?
Thank you for any response this my seem very long winded i apologize for this, this is my first time using a forum. I will provide pictures when the lights come back on.

If you have removed the build up of the salt nutes , you are now just feeding with an EC of 0.3. This is a incredibly low EC , especially if the plant has begun to flower. I generally have an EC of 2.0 - 3.0 in the mid to late flowering stage. The ratio of nutrients is great to know, but it really boils down to the EC levels. With Coco I recommend watering till run off (20%-25%) , as you should not get nutrient lock out in Coco. If you water till run off , you are essentially refreshing the plants nutrients and removing any build up that may become harmful to your plants.

This is a generalized guide for EC in Coco:
Veg - 0.5 - 1.3
Early Flowering - 1.4 - 1.8
Mid Flowering - 2.0 - 3.0
(All dependent on how the plant reacts , however I never flush Coco grows)

You can slowly build up the EC , but I recommend that you increase it to at least 1.0 EC , if you are planning on continuing the vegetative phase to the 2 month mark. As feeding 0.3 EC is very weak and you do not have to worry about nutrient locking , if you have run off , as there would be no build up.
Hope this helps!

This was so helpful thank you so much, ive just swtiched to tge advanced nutrient line and by going off my ec, my plants are lookinf healthier than ever. thank you!!