Fins for my board

First,,,, sorry for my poor english!!!!
Ok, im wondering if y can take off the 2 litle fins on the both side of my board and change the midle one for he longer one??
and are they all fit or I need something specially
for my board??
my board is he Chanlenger 9,0'.
Thank you and sorry to be so newb!!
Merci
Ok, im wondering if y can take off the 2 litle fins on the both side of my board and change the midle one for he longer one??
and are they all fit or I need something specially
for my board??
my board is he Chanlenger 9,0'.
Thank you and sorry to be so newb!!
Merci