...then I went into the UniFi controller and set up 4 SSIDs, one for each VLAN ID:
Any user that connects to SSID t-10 gets assigned an IP on VLAN10, t-20 on VLAN20, etc. With the firewall rules in place, devices on VLAN10 can't talk to devices on VLAN20, 30, or 40 nor can those VLANs talk back.
Any user that connects to SSID t-10 gets assigned an IP on VLAN10, t-20 on VLAN20, etc. With the firewall rules in place, devices on VLAN10 can't talk to devices on VLAN20, 30, or 40 nor can those VLANs talk back.