How to get rid of search bar on home screen in 6.0 I have already tried options mentioned in many other answers here/ posts online. I have a nexus 5
disable google now: option is disabled
use custom launcher: shows even in Nova launcher!

Edit: here is what I tried: 

https://www.androidpit.com/how-to-remove-the-google-search-bar-from-your-android-homescreen

it doesn't work because Google Search doesn't appear in the list of installed apps in marshmallow
You can remove the Google Search bar by installing an application Xposed GEL Settings.

Open XGELS > Google Search Bar > Hide

Please note: This application requires ROOT and Xposed Framework.