Oh yeah, now I see it. The picture is rotated about 80 degrees CCW from the horizon. 
Disregard my previous note. 
I would only caution about using city connections for filling up the tank. With city pressure the vent restriction will build up the tank pressure if you don't pay the attention (what happens more often than we will admit) the tank will blow.
I would either plan bigger vent, or one of my motorhomes had electrovalve that would shut the water off automatically.
Or at least make a habit about using city fill with main cap open.