iftop, ProCurve 3500yl, and vlans

I've set up iftop for the purpose of seeing all data moving in and out of my network and the internet, but I'm not sure it is. I think it is only seeing traffic on my default vlan (1). Looking to learn here. Anyone want to get some glory?

Here is my topology:

Comcast cable modem port "Lan 3" to SonicWall 2400 port X1. SonicWall 2400 port X0 to HP ProCurve 3500yl port 24. Port 24 is mirrored on port 19. iftop (computer) is on port 19.

On switch:

mirror 1 port 19
interface 24
   monitor all both mirror 1
   exit

I also have the following vlans:

vlan 1
   name "DEFAULT_VLAN"
   untagged 1-19,21-24
   ip address 192.168.0.41 255.255.255.0
   no untagged 20
   exit
vlan 10
   name "VoIP"
   qos priority 6
   tagged 1-24
   voice
   no ip address
   exit
vlan 20
   name "PC"
   tagged 21
   no ip address
   exit
vlan 30
   name "Wifi"
   untagged 20
   tagged 21
   no ip address
   exit