Will flat feet disqualify me from joining the royal marines?

iive been told i have flat feet but to me it just looks like shallow arches. when i stand only the heel ball and outside edge of my feet touch the ground, if i slouch i can get all of the bottom of my feet to touch the ground but it takes effort to do this. ive never had a problem from them even when on them for 8-10 straight, nothing more than expected leg soreness and fatigue. i need to know because i plan on joining the royal marines and need to know if it will disqualify me. i would appreciate an answer preferably from an actual RM who knows for certain, many thanks.