What Canalman said. Also it depends on the spot. Some places are low tide spots. Some are high tide spots. Some are 2 hours down. And you know how you find out? It's called trial and error. Eventually you are at the right place, at the right time with the right tide and moon and wind and bingo, you get good fish.
I know this sounds like an evasive answer but it's the God's honest truth. That's why it's important to keep a log of every trip you take.
