[H] Ubiquiti EdgeMax SFP router

[Winterlight]

I have an old Trendnet router that hasn't had a firmware update since 
2014 so I figured it was time to update. Because I use a Ubiquiti 
AirMax wireless I bought a Ubiquiti  EdgeMax SFP router with PoE 
support on sale at Newegg. It has a SFP Port. I bought it quite a 
while ago in anticipation of using it so there is no sending it 
back... here is the manual http://www.rode.us/EdgeRouter_X_DS.pdf

It wasn't very expensive but it has a level of sophistication that is 
beyond me. I understand that I can use my AirMax without a power 
connection by running it off one of the PoE ports. And I could also 
use my Panasonic Security Cameras in the same way... But where do I 
plug in the cable modem? The SFP port.. but isn't that fiber. Did I 
buy the wrong kind of router for the job. Help!