dropping all databases and starting afresh

Hi,
Just joined the list, and this is first time foray into SQL databases, so apologies for the (most likely) lame questions.
I have installed 9.4 with PostGIS on Ubuntu 14.10 64bit Desktop.

After install I didn't like where the default databases went to, so I did:

    mkdir /mnt/geo_md1/postgres
    chown postgres:postgres /mnt/geo_md1/postgres
    su postgres
    postgres@gs01:/home/geograph$ createuser -s -d -e --replication zls
    postgres@gs01:/home/geograph$ pg_dropcluster –stop 9.4 main
    postgres@gs01:/home/geograph$ pg_createcluster --start -d /mnt/geo_md1/postgres 9.4 gisdata

After fiddling for a few days, I now want to start afresh, by deleting all data and creating a new area in a different directory, but:

neither:

postgres@gs01:/etc$ pg_dropcluster –-stop 9.4 gisdata
Usage: /usr/bin/pg_dropcluster [--stop] <version> <cluster>

nor

postgres@gs01:/etc$ pg_dropcluster –-stop 9.4 postgres
Usage: /usr/bin/pg_dropcluster [--stop] <version> <cluster>

works.
I've done no createdb commands, so dopdb shouldn't be what I want for this cleanup (I'd think).

Please can someone spot my oversight.
I'd like to cleanup, change the mount-point for my RAID, and then create a fresh start.

Thanks in advance,
Zoltan

postgres@gs01:/etc$ ls -la /mnt/geo_md1/postgres
total 84
drwx------ 18 postgres postgres 4096 Feb  2 18:07 .
drwxrwxrwx  4 staff    staff    4096 Jan 29 18:32 ..
drwx------  5 postgres postgres 4096 Jan 29 18:34 base
drwx------  2 postgres postgres 4096 Feb  1 14:13 global
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_clog
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_dynshmem
drwx------  4 postgres postgres 4096 Jan 29 18:34 pg_logical
drwx------  4 postgres postgres 4096 Jan 29 18:34 pg_multixact
drwx------  2 postgres postgres 4096 Feb  1 14:13 pg_notify
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_replslot
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_serial
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_snapshots
drwx------  2 postgres postgres 4096 Feb  1 14:24 pg_stat
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_stat_tmp
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_subtrans
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_tblspc
drwx------  2 postgres postgres 4096 Jan 29 18:34 pg_twophase
-rw-------  1 postgres postgres    4 Jan 29 18:34 PG_VERSION
drwx------  3 postgres postgres 4096 Jan 29 18:34 pg_xlog
-rw-------  1 postgres postgres   88 Jan 29 18:34 postgresql.auto.conf
-rw-------  1 postgres postgres  129 Feb  1 14:13 postmaster.opts