Trying to get a estimate on ppm for 12 foot plants outdoor

About to run koolbloom, 0,10,10, and in week 6 going to use,2,45,25 koolbloom

Boosters are a supplement, you don't need to go crazy with them, add 0.3-0.5 EC worth of boosters to your feed.

How long should I use the liquid koolbloom I was saving the bloom booster for week 6&7

I haven't used boosters in years, I'm on the KISS method now with Jacks start to finish.
When I did use them I would start when buds were popcorn size...so that's like week 3-5.
Then switch to the finisher.
I found more headaches than rewards with boosters over the years, burnt plants, Mg lockout and crap like that.
Just go easy with them and don't love your plants to death.
I remember back in the dark times when we grew for profit a buddy of mine fried a whole room of plants with H&G Shooting Powder.

Yeah definitely not going over 1000ppms all the way through flower