What line group should be used for reservoir fishing?

Tell me about my personal experience of wild fishing for many years: I grew up by the river, which can be regarded as several generations of fishing. Before 20 10, people used traditional fishing methods, and fishing rods were all made of bamboo (bamboo with small diameter, symmetry and dense bamboo joints was generally used, and the process was generally to remove branches, bake straight, repair, dry, pierce rings, paint, reel and assemble accessories online, and the finished product was similar to the current rock fishing rod, but it could not be extended and contracted), because it was natural. The bait is all live bait (worms, maggots, loach). I don't know what fish will take the bait, but I always use a big hook line (3-4# line hangs worms and maggots, and 6# braided line hangs loach as bait), but there is no guarantee that I can catch the fish (carp and mandarin fish, which are often longer than the washboard, start to contact Taiwan Province for fishing after 20 10, and now they have moved to reservoirs and rivers for many years. I prefer to use hard carp poles. According to my experience in recent years, even if I don't fish small crucian carp in rivers and lakes, I must at least ensure that the main line is 2.0+ and the sub-line 1.0+ (I often meet carp and carp when fishing small crucian carp in the wild. Wild fish eat fiercely, often with sudden strength and strong endurance. This kind of cultured fish is unparalleled.