What to do when pouring polygon if you didn't use a GND?
A polygon pour can be &quot;associated&quot; with any net you choose. It doesn't have to be linked to &quot;ground&quot; and, on all the packages I've used, it doesn't need to be linked to an actual specific net. How do you think people apply a power-plane in their design? Answer: they link the polygon pour to a net that is called &quot;+5V&quot; (or similar).
If you have a polygon pour that isn't connected to a net you might be asking for trouble in terms of it acting like an antenna so, I would recommend that it is connected to a net of some type.