How to set mail qouta about 250 MB for all accounts in Zimbra mail server.

After I installed the Zimbra mail server, I forgot to setup a mail qouta for all accounts that mean thay have unlimit space. So I think this is a time for setup mail qouta because my disk of mail server was deficient.

for email in `/opt/zimbra/bin/zmprov gqu earth.enspry.com | /bin/awk {'print $1'}`
do
    echo ${email};
    # set mail quota to 250 MB [262144000= 1024 byte x 1024 kb x 250]
    zmprov ma ${email} zimbraMailQuota 262144000
    sleep 1;
done