The central defender was only appointed on June 28th following the departure of long-standing boss Jamie Howell to Eastbourne Borough.
El-Abd had hoped to mix the role alongside his full-time coaching job with Brighton and Hove Albion's community department.
However, after less than a fortnight as Rocks manager, El-Abd has stepped back and will revert to just being a player and club captain.
General manager Jack Pearce, coach Darin Killpartrick and player Gary Charman, who was named as El-Abd's assistant, have taken over.