Moving Postgres 10 data dir on Ubuntu 18

I am trying to move the initial Postgres data dir from

/var/lib/postgresql/10/main

to another harddrive. The harddrive is accessable within the terminal via

/media/chris/Datenspeicher

I used this guide to switch my data dir. Postgres is starting up after modifying the postgres.conf file but im not able anymore to access the database through pgadmin or the terminal.

When trying to access the database its asking if the database is running on port 5432 and accepting connections.

Why? What am I doing wrong?

Update:
After clean install of ubuntu and postgres all errors still remain.
The postgres log output is:

2018-07-06 14:16:04.958 CEST [5664] LOG: listening on IPv4 address "127.0.0.1", port 5432

2018-07-06 14:16:04.998 CEST [5664] LOG: listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"

2018-07-06 14:16:05.124 CEST [5665] LOG: database system was shut down at 2018-07-06 14:00:21 CEST

2018-07-06 14:16:05.167 CEST [5664] LOG: database system is ready to accept connections

2018-07-06 14:16:05.714 CEST [5672] [unknown]@[unknown] LOG: incomplete startup packet

Please check the socket file is in the /tmp. If it is there then create a link to /var/run.

OR,
I prefer this method to move the data directory on Ubuntu.

I hope you have the backup copy of the old directory which is in /var/lib/postgresql/10/main.

service postgresql stop
rm -rf /media/chris/Datenspeicher/*
chown -R postgres:postgres /media/chris/Datenspeicher/
chmod 700 /media/chris/Datenspeicher
/usr/lib/postgresql/10/bin/initdb -D /media/chris/Datenspeicher
rm -rf /media/chris/Datenspeicher/*
sudo rsync -av /var/lib/postgresql/10/main/* /media/chris/Datenspeicher
in postgresql.conf file,  data_directory = '/media/chris/Datenspeicher'
service postgresql start

StackExchange Database Administrators Q#211397, answer score: 2