Spring tides are when the moon is full or new and the moon and sun are combined.At these times the high tide are very high and low tides are very low. This is called a spring high tide, spring high tides are very strong, They occur when: The Earth, the Sun and Moon are in a special line.
Smaller tides, called neap tides, are when the earth, sun and moon form a right angle. This causes the sun and moon to pull the water in two different directions. Neap tides happen during a quarter or three-quarter moon.