What Size Line Should I Use for Deep Sea Fishing?

Deep sea fishing is a great way to spend a day out on the water, but it can be intimidating to the uninitiated. One of the most common questions for beginners is “What size line should I use for deep sea fishing?” The answer depends on the type of fish you are Targeting, your equipment, and your environment.

For light tackle fishing, a thinner line will work best.

This type of line is ideal for smaller species such as bonito or mackerel. A line size of 8-20 pound test (lbs) is usually recommended for light tackle fishing. The thinner diameter of the line allows it to cast more distance and move more freely through the water.

When Targeting larger species such as tuna or marlin, a thicker and stronger line is needed. A 50-100 lb test line will provide enough strength to land these larger fish. Thicker lines are also better at preventing break-offs due to abrasive rocks or other underwater obstructions.

The type of equipment you use will also have an impact on the type of line you should use. If you are using spinning reels with light tackle, then lighter lines may be adequate; however, if you are using conventional reels with heavier tackle, then thicker lines may be necessary.


The environment in which you are deep sea fishing will also have an effect on the size of your fishing line. If you are fishing in very shallow waters where there is more risk of snagging on rocks or other obstructions, then a thicker and stronger line may be necessary. On the other hand, if you are fishing in deeper waters where there is less risk of snagging, then lighter lines may be sufficient.


The size of line used for deep sea fishing depends on several factors including the type and size of fish being Targeted, the equipment being used, and the environment in which one is fishing. Thinner lines work better for small species while thicker lines should be used when Targeting larger species such as tuna or marlin. In addition, environmental conditions should also be taken into consideration when choosing a suitable line size.

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Emma Gibson