No reason why you can't If you run the supply and return into the sump, it will act like a closed loop and should have no effect on the normal tank operations.
If you put the supply in the sump and the return in the tank, it will act like a return pump, so you will need to make sure your overflow can handle the additional flow.
If you put the supply in the tank and the return in the sump, it will reduce the flow through your overflow.
If you are using it to just run carbon or other filter media, you can run it just in the sump, and it should work fine