Turris omnia behind Router

Hello there,
Im from Switzerland and im having a 10 gbit fiber connection using my saltbox from a provider called SALT.
I have a fixed ip. I just setup a computer that i would like to use as a server.
I also have other devices that im using, over the wifi of the salt router.

I want to SSH into my server from the outside and i figured out how to do it. But i dont want users using my server having access to my other devices in my home.

I would like the maximum of security running my server from home. So the idea is hooking up my turris wan to ethernet port of the salt box, creating a second ip range for the turris, then setting up the DMZ.

As soon as i plug in my turris into my salt router (turris wan > Salt ethernet) it won’t work. I turned off bridge and changed the turris Lan ip to 192.168.2.1 and turris won’t go online.

If i plug an ethernet cable from an ethernetport of my turris into an ethernet port of my salt box it works but its very very slow and the PC hooked up to my turris is in the same IP range as my devices hooked up to the salt router.

How to i solve this?

Omnia have 1 Gbit Ethernet WAN and 2,5 Gbit SFP.

Thats fine with me. I dont mind. I just would like it to work and be safe for me to run the server from home.

apparently you need to configure turris to provide different address range than salt router uses.