A ladder is designed for a tank having a vertically extending side wall and a top of a convex curved profile, with an access point near the top center of the convex curved top, the ladder having a pair of parallel side rails, each side rail having a straight section at one end and a curved section at the other end, the curved section extending over the top of the tank and toward the access point, with plurality of rungs extending between and secured to the side rails, with at least one rung positioned in the straight section of the side rails and at least one rung positioned in the curved section of the side rails. A separate hand grip may be mounted on the tank between the ladder and the access point of the tank.