Diagnose my leaf problem. HELP!

I'm about to hit the 5th week of flowering...and over the past week or so my top leaves have been going brown and crispy...the bottom of the plant is still lush and green.

Set up is:

250w Red CFL
1ml biogrow / 3ml biobloom / teaspoon of molasses per litre of water
Not sure what the PH is.

Any help would be great!

itd probably be a good idea to find out the ph

I have some PH test stuff...how do I take soil sample? Just get some soil from around halfway deep in the pot?

i dont know i use a meter
theyre like 5 to 10 bucks at any garden supply

Okay, my PH is too acidic. Any suggestions on getting it down a bit?

flush it or use dolomite lime in your water but id look it up as well cuz im really stoned

srry in avance in i not supposed to post this but here is a link that might help but def get ur ph where is supposed to be. this is a link to all kinds of plant problems with pictures Planting Cannabis Seeds
like i said srry if im not supposed to post this site after what happen to them this where i learned all i kno

why what happened?