The speed controller is just an ordinary light dimmer, it will work like i said earlier use a Bridge Rectifier on the motor because your motor is for DC.
http://cpc.farnell.com/unbranded/cm2506/bridge-rectifier-25a-600v/dp/SC07537
http://cpc.farnell.com/unbranded/cm2506/bridge-rectifier-25a-600v/dp/SC07537