Bradley Sach put the Gulls ahead from the penalty spot in the 43rd minute before sealing the win with another effort in stoppage time.
Fourth placed Billericay Town lost 3-1 at Chichester City despite the taking the lead through Tyrell Miller-Rodney while third from bottom Bowers & Pitsea lost 2-0 at home to table-topping Dover Athletic.
In Isthmian North, Basildon United slipped to 12th in the table after a 2-1 defeat at Mildenhall Town while Concord Rangers, who are 13th, drew 2-2 at Maldon & Tiptree.
The Beach Boys seemed set to triumph thanks to goals from Billy Knott and Thomas Stagg but the hosts equalised six minutes into stoppage time.
In the Essex Senior League, fourth placed Great Wakering Rovers lost 2-1 at league leaders Stanway Rovers while 10th placed White Ensign were beaten 2-0 at home to Takeley.
However, there were wins for both Benfleet and Hullbridge Sports.
Benfleet moved 14th after beating Athletic Newham 3-0 with Nathan Saunders, Sonny Hartman and Toby Dickinson all hitting the back of the net.
Hullbridge went 17th in the standings after seeing off West Essex 4-1.
Mechack Asuka bagged a brace for Hullbridge while Ruben Santos and Owen Bellamy also netted.Â