LG G3 Battery drain *help please*, what do I do?

Hi,
Please help me, because my LG G3 has bad battery life, I can get max 3hours 45 minutes sot. I was on lollipop till yesterday and I was rooted, debloated as much as I could, greenify, l-speed and kernel adiutor installed. I think I tried everything including underclocking cpu, gpu and setting different governors with absolutely no effect. So I updated my LG to marshmallow yesterday to see if it makes a positive impact on my battery. No results, still about 3hours sot.
Any help would be highly appreciated
LG - d855 16gb version
android version - 6.0
Please help, I can post more info I you want

Moved to the G3 forum.

Without rooting and all the editing, did you already just buy a new battery?
It's possible to see what apps are using your battery via Settings > General > Battery > Battery Usage

I have it even worse. My LG G3 battery dies after I take just 4 or 5 photos. The power drops from 99% down to 77% and the phone dies. I must re-boot the phone yet the same thing happens until I re-charge the battery or put in a new battery. I often carry 4 or 5 spares!

I had an Ebay battery, new, that acted just like that.
Bought a name brand battery, that did NOT act like that.