I did some test with FPS, the six fountains I didn't really notice. The laanx temples flames are more intensive. But that is due to having two flames, embers+sparks with collision detection set, and also a light source which will cast real time shadows.
You can set all sorts of level of detail on them so things like the light only displays when you are really close, the same with the sparks and embers. This should optimise the effect so it looks best when only up close. Right now the sparks, embers and light would have been rendered during the whole of the video.