What factors determine the size of the tide?

Due to the gravitational force of the sun and the moon, most of the coastal areas in China are tidal phenomena in which the seawater fluctuates day and night. The tidal changes in Dalian are obvious. The first day to the fifth day of the lunar calendar (or the sixteenth to twentieth day of the lunar calendar) is the spring tide, which is called "the flood season" by the locals. The sixth to twelfth day of the sixth lunar month (or the 21st to 26th lunar month) is a small tide, which is called "dry season" locally. The daily tidal time change is delayed by about 45 minutes, and the period is unchanged. It is not difficult for fishermen to master this law. As long as they find out the exact time of low tide or high tide in a day, and then delay it for about 45 minutes, they will accurately grasp the time of low tide and high tide the next day and the next few days. For marine fishing, there is no doubt that the change of tidal law is closely related to whether marine fish eat hooks. Because the tidal current velocity determines the amount of nutrients (dissolved oxygen) and plankton in seawater. The amount of dissolved oxygen and plankton in seawater determines the physiological function of marine fish foraging, which is dialectical unity. Therefore, in order to gain something from sea fishing, we must accurately grasp the correlation between tidal changes and sea fishing. This is why anglers repeatedly emphasize spring tide rock fishing and small tide boat fishing when choosing fishing opportunities.