ppm...rollitup.org right or this cannabis cultivator book

so i been searching and looking around to find out what the right ppm is too much for a plant. i'v been using general hydroponics advance nutriants and make my ppm 2230 for the bloom cycle. i drop this h202 so its down to 1840 ppm. Heres the thing rollitup under newbs 101 questions pmm says that 1500 pmm is the most my cannabis cultivator says 3000. iv read up on advance nutriants and they say they burn on the tip normal....which is happing with curling of leaves on younger leaves and yellow spoting on older leaves. anybody got an idea? this is my first plant and i really trying to see it to the end all help apricated!

Ppms can vary widely depending on strain and set-up.

Start low and nute a little more each time until you see the burn on the tips and back off a tad.