How to fill hole in UE4 Ocean Body volume?

I want to make a level filled with water without any visible land by default. The UE4 Water Body Ocean seems like what I want but the object has a hole in the middle of it that looks like it’s for a landscape or a lake. Is there a setting somewhere to fill the hole and only use the ocean body volume? Or do I need to put a lake volume there to fill the hole?

The documentation does not clarify how to handle this hole - Water | Unreal Engine Documentation