Multiple external subnets and gateways

This is probably something very simple I just am not grasping.. However, we have an existing subnet that our ISP has assigned to us, for example sake we'll call it 1.1.1.0/24. They gave us the gateway of 1.1.1.1. We set this up in the LTM as the default gw and create VS with any IP in 1.1.1.0/24 and all works well. Now we are out of IPs in 1.1.1.0/24 so we ask the ISP for more IPs and they give us 1.2.2.0/24 and tell us to us 1.2.2.1 as the gateway for that block of IPs. How do I set this second block up in the LTM so it routes traffic via the appropriate gateway? These IPs are all delivered to us via a single Ethernet drop.

 

 

Thank you