convert system from not using a password to using passwords

I inherited a setup where php pages use postgresql databases. Currently the php pages use pg_connect with user=postgres and password=''. I want to change this to using a different user that has a password.

1. First created a user that can access all the databases:
postgres=# CREATE USER web_u1 with PASSWORD '********' CREATEUSER;

2. Next I changed pg_hba.conf with the entries
# "local" is for Unix domain socket connections only
#local all all trust
local all all md5

# IPv4 local connections:
#host all all 127.0.0.1/32 trust
host all all 127.0.0.1/32 md5

# IPv6 local connections:
#host all all ::1/128 trust
host all all ::1/128 md5

3. I changed the php code as follows
$conn = pg_connect("host=localhost port=5432 user=web_u1 dbname=db_name password='********'");

This all worked. My problem is the obvious, all pages are broken until I update each page that has a pg_connect statement. Is there a way to configure the pg_hba.conf file to accept the "user=postgres with no password," if "user=web_u1" with a password is not provided?

Also is there anything I missed in my steps with creating the user with a password and updating the pg_hba.conf file?

Thanks

Marc