BayLee420
Chef de la ganja
Can you be more specific about your soil? Is it a brand name? The basic nutrients, are they slow release?
That's a pretty broad range on your pH and depending on what the run off is reading, could be the cause of your issues. You may also be watering a bit too often. Cannabis plants like to go through wet/dry cycles. The best way to know when to water is to get a feel for your pots when they are almost dry. Only water when they feel that way. When you water, make sure to give enough so that about 10-15% runs out the bottom of the pots. Collect and test the pH of that run off water and let us know what that reading is. The more accurate you can be with those pH readings the better we can help you.
Muddy, Blue and namvet25 are on the case. You have the best of the best helping you now. Listen to what they say and you'll be golden.