Tides depend on both the moon and sun. So does the phase of the moon.
Tides are largest at full moon and new moon, when their gravity gradients combine to enhance each other's tides. A week later, their gravity gradients interfere, decreasing the amplitudes of the tides.
Aside, grew up in Florida and was always a little surprised whenever I met someone who'd not seen the ocean until they were an adult, but eventually realized maybe that wasn't so odd considering I didn't see snow for the first time till I was an adult. To me, skiing is something you do on the water, so when I say "snow skiing" people often look at me oddly, as if there's any other kind. Well, there is. :-)
I have been told by a friend of a student from Louisiana who was an avid water skier. Her friends at UC Berkeley discussed going to the lake to ski. She joined and was quite confused by the snow on the ground.
Tides are largest at full moon and new moon, when their gravity gradients combine to enhance each other's tides. A week later, their gravity gradients interfere, decreasing the amplitudes of the tides.