Possible Clues:

• Wave painted with minimum of ebb, suggesting this?
• Not high enough for a spring
• Small ebb and flow of the sea
• Twice-monthly shoreline occurrence
• Sounds as if it's knotted at last, but there's little or no spring in it
• First or third quarter phenomenon
• It comes in and out without any spring to it
• No spring
• When high and low water are nearest
• One of two, producing sea ebb and flow