Subline is also called foot line, brain line or mouth line. It is the fishing line (sometimes called the hand pole line group) connecting the main line and the hook in fishing tackle. The number of numbers used by the secondary line is usually smaller than that of the main line, which is generally 0.4-0.8 times that of the main line. The purpose of using the auxiliary line is to ensure that the main line is unnecessarily pulled and tightened when hanging the bottom or catching big fish.
There is a main line and a secondary line in the fishing group, and the most important thing is that they have these two functions. One is that the material of the secondary line is somewhat different from that of the main line, which is softer. Therefore, when fishing, the line of fish swallowing hook is smoother and the drift is more obvious. The second reason is that when fishing, I catch a big fish, and I want to break it when it exceeds the tolerance of the line group, and I am willing to break the secondary line instead of the main line.
Fishing line combination refers to the tension value of the main line, which is about twice that of the auxiliary line. Target fish are divided into two categories, one is small fish and the other is big fish. If you are fishing for small fish such as crucian carp, then the combination of lines is probably like this. For crucian carp fishing in winter and early spring, the line group can be smaller, with 0.3-0.4 secondary line and 0.6-0.8 main line.
Because crucian carp in winter or early spring don't struggle hard and eat lightly, the string will be more sensitive and the signal will be better within the tolerance range of fish tension. If you are fishing for big crucian carp in mid-spring or summer, the parting line and main line can be slightly thicker.
If you are fishing for big fish, such as carp or grass carp, the line group should be strong enough. Generally speaking, it is conservatively estimated that 1.5 sub-line and 2.5 main line can catch fish under 4 kg, 2.0 sub-line and 3.0 main line can catch fish under 6 kg, and 3.0 sub-line and 4.0 main line can catch fish under 12 kg. 4.0 secondary line, 5.0 main line, fishing 20-30 kg is basically no problem.