what is the best way to dump postgresql

Now I have a table have more than 30000000 rows, when I using this command to dump in postgresql:

$ /usr/local/Cellar/postgresql@13/13.0/bin/pg_dump -h postgres.dolphin.com -U postgres -p 5432 -d dolphin -f ./dolphin-$(date '+%Y%d%m%H%M%S').sql

it is very slow(more than 2 hours), if the database is very large, how to backup database the easy way?