Robalos normally plane up pretty fast if powered correctly. However, they tend to be heavier than most 18 foot boats - around 3000 lbs boat and motor. That boat is rated for 150 hp, so the 130 should be quite adequate for a decent hole shot. Check your engine setup and prop. When on plane, the cavitation plate on the engine should be riding on the surface of the water. If not, adjust engine height. At wide open throttle (WOT) your should be turning between 5600 and 6000 rpm. If under that change prop by reducing diameter or reducing pitch. If it goes to 6000 rpm real fast, but still struggling to get on plane, then increase diameter or pitch to find the combination that gets you right around 6000.
You could also have a weight distribution problem in the boat. In calm water note how she sets in the water - it should be level from bow to stern, if not, see what you can do to change distribution. Moving the batteries forward, if possible, often helps. Any heavy gear should also be stored forward.
If you have trim tabs, set them down full for the hole shot then adjust as you get on plane.