The Perfect Server - Ubuntu 16.04 (Xenial Xerus) with Nginx instead of Apache

Hello,
I try to install ISPConfig 3.1 with Nginx and PHP7 on Ubuntu 16.04.. Nginx and PHP7 and PHP-FPM are installed out of the official Ubuntu-Repositories. The installation of ISPConfig succeed but on my Websites no PHP Code is running.

What I have already tried:

Adding an additional PHP-Version with follow paths in ISPConfig:

Init-Script: /etc/init.d/php7.0-fpm
php.ini Directory: /etc/php/7.0/fpm
Pool Directory: /etc/php/7.0/fpm/pool.d

Maybe someone has an other idea.