Adsl Router > Dual Wan Load Balancing Router > 24 port Switch Hub

Hello!

My present set-up is this, I have an adsl router connected to my 24-port switch hub which is then connected to the 20 pc's. The Full Rate Adsl Router is the one provided by our ISP(lets call this ISP-1). However, they are giving us a very low bandwidth of 384kbps and it disconnects very often. So we looked for another ISP (lets call it ISP-2), sadly it disconnects as much as ISP-1. So we thought of using both ISP and buy a load balancing router to be able to make use of the benefit of the Fail-Over set up.

I now have a D-Link DI LB604 Load Balancing Router.
My problem now is this, I cant use ISP-1 without plugging it to their provided router. Can I connect this router to my new load balancing router. I am afraid to connect the two coz i thought I might damage the new load balancing router. It costs too much and I have to be extra careful What do you guys think?

If the two routers can be connected, is there any configuration needed? Can you help me out please?

Thanks,
nazeth-sweet pinay

nazeth