Ok great! I have the Motorola moca adapter — I don’t Think I can enable it on their. No GUI I believe.I think it depends on how VZ provisions the ONT. For Internet it can be ethernet/RJ45 or Coax. Not both.
For TV, it's coax going to their STB. TV is never carried over RJ45
For both TV and Internet it's one of these:
If Router is going to be coax connected to ONT, a splitter is used - one output to Router the other to STB. VZ provisions Internet to coax connector (ONTs RJ45 is disabled)
. If Router is RJ45 connected, ONT RJ45 to Router and Coax to STB. VZ provisions Internet to RJ45
From what I have read, if TV/Coax, it is on a completely different subnet/network from Internet.
Long story short, I don't think you have setup a loop. Believe me, if you did you would know - your devices connected to the Internet would slow down dramatically. The network is being flooded with redundant packets. This is where Spanning Tree attempts to turn off ports on the network devices (other switches typically) that are the source of the loop.
Also, for Spanning Tree to work you need it enabled on all switches and routers.
You can enable it on the Asus router - but unless you have other routers and switches on your network (with Spanning Tree enabled) it really has nothing to do.