have only one datasource at firebase

I have a chat app, where I'm saving the groups and rooms in a Postgres database, and the messages are in Firebase.
I tried use emberfire, but once you add it, all the this.store.find are routed to Firebase database, and I can't do that.

I also tried added firebase script direct to the chat-room-component.hbs but of course, I cannot add javascript to handlebars template...

What can I do in this case?