Routing Issue!! Please Help!!

I hope this is easy for somebody…I have a T1 circuit and Fiber circuit both coming into my office. I have 2 gateways set in my router…the first one that lists is for the T1 and the other is a Fiber with a prerouting mangle mark to send some traffic out that circuit. I have been unable to ping any of the fiber Ips I put on my router here and have now figured out that it looks as if the packets are trying to go out the T1 gateway because when I disable that gateway and disable the prerouting mark on the Fiber gateway I can start pinging again. Can somebody please let me know what I need to do to get my fiber ips working properly on this router.

Set up static route with your IP range e.g. 1.2.3.4/32 or whatever to go to correct gateway. Have same problem with load balancing where I ping local ADSL but it pings over internet until I setup static route or routing mark.