Using Several Mini's

I have 2 Mini's both connected to the R-Plus using Moca. On the R-Plus, TiVo support had me set it up using both Ethernet and Moca. My question: I want to add a 3rd Mini, the room where I would like to put the new Mini does not have an RG-6 cable. Can I use Ethernet on that 1 mini to make the connection to the R-Plus?



Thanks