You also need a route in the routing table for non-locally connected subnets.
Consider F5 vlans A & B
vlan A hosts should have route to bigip for vlan B hosts
vlan B hosts should have route to bigip for vlan A hosts
vlan A hosts & vlan B hosts should have a route to bigip for vlan C hosts
Assuming your 0.0.0.0/0 forwarding virtual is in place, the F5 will forward packets between these vlans because they are locally connected. However, since vlan C is not local to F5, F5 also needs a route to this location in order to forward packets from vlan A and vlan B hosts to that destination