Accessing Umbrel containers from other docker containers

I want to add domains and ssl certs to some of these docker containers so I can access them over the internet. For example, I would like my own mempool instance to be available at a domain like I have a nginx docker that runs on port 443 and I have a certbot docker which can renew certs and create more certs for SSL.

What network on docker do I need nginx to be on and how do I access these docker containers? I would like to get this to work so I can hook up my electrs server to my lightning wallets, for example.

sorry this isnt answering your question, but this might be of interest to you if you don’t mind cloudflare:

In the past I have just set-up a reverse proxy from another server, or just used tailscale for electrs in particular. Let me notify the team for a better answer.