radio trouble on my 95 10 speaker

i replaced all my interior speakers along with the head unit but the head unit was too week so i ran wires from an amp in the rear and just hooked them up as if they were the head unit but now the $180 6.5 subs in the back seat side panels do not work but they worked with just the head unit any one know y or what i can do to fix it so i use my amp

your running all ten speakers off of one amp? if you are, is the amp meant to run that many speakers, and does it have a sub channel. It could just be that the amp itslef is too weak to power those subs.

no the amp has plenty of power for all the speakers

does the amp have a low pass filter for the subs? I know that if my amps LPF is off I get nothing out of them at all, Its really hard to tell that their even going.