How do custom domains work?
If you have a domain registered elsewhere and want to use it on an upgraded site please point your domain to Tank as follows.
Request your ISP to point the a-records (with and without the ‘www’) of your domain to 18.104.22.168.
Another way to put it is to map the hostnames @ and www to the destination 22.214.171.124
(Please note this option means your email will remain entirely intact and stay with your current ISP.)