01Water Temperature·Depth·Tide, Basic Conditions for Hairtail Tackle

In August, hairtails are most active in water temperatures of 16‑22 °C and depths of 20‑60 m, during which their metabolism peaks, increasing prey‑search speed by about 30 %.

The two‑hour window around tide (sunset ± 2 h) features currents of roughly 0.3‑0.5 m/s, allowing hairtails to rise near the surface and feed on small plankton.

When water temperature drops below 18 °C, the hairtail's activity radius shrinks by about 10 m, so real‑time monitoring with a thermometer and depth gauge is essential in waters with large temperature fluctuations.

Target temperature
16‑22℃
Target depth
20‑60m
Golden Tide Time
Sunset ± 2 h

02External‑line Hairtail vs. Hairtail Lure, Tackle Differences

External‑line hairtails combine 4–6 go PE (polyethylene) braided line with 8–12 go high‑elastic carbon leader to achieve a weight of 200‑300 g and elasticity of roughly 30 GPa.

Lure rigs use 2–4 go carbon braided line with a 5–8 go carbon leader, keeping total weight between 80‑150 g, while spoon‑type lures of 0.2‑0.4 m length vibrate rapidly along the wave.

The external line maintains steady tension in fast‑flowing rapids, preventing sudden line slack when the hairtail bites, whereas the lure provides visual stimulus with high‑speed rotation in low‑current areas.

03Tackle Application by Major Spot

Chagwido, Jeju
Southern East Sea Rapid Currents
30–80m
August
Yeosu Geomundo
West Sea Current Inflection Point
20–70m
August
Entire South Sea coast
Coastal Nearshore
15–60m
August

At Jeju Chagwido the current reaches 0.4‑0.6 m/s, making an external‑line rig advantageous. Using 4–6 go PE braided line with a 10–12 go carbon leader and increasing weight to about 250 g reduces wave resistance on the line.

At Yeosu Geomundo the current is gentle at 0.1‑0.2 m/s. Matching 2–4 go carbon braided line with a 5–7 go leader and keeping weight under 100 g lets the lure rotate quickly at 1‑2 s intervals, maximizing visual stimulus.

The South Sea nearshore is shallow (15‑30 m) with large temperature swings, so targeting 18‑20 °C with 3–5 go carbon braided line and 6–9 go leader at 150‑200 g provides moderate elasticity.

⏱ How to Use the Golden Time
Sunset − 2 h
Slowly let out the line to create a subtle surface movement, securing about 0.5 m of line before the fish enters the visual field.
Sunset ± 30 min
Lift the line slightly to capture the moment the hairtail breaks the surface, maintaining line tension at 0.8‑1.0 kgf.
Sunset + 2 h
When the tide ends, reel in the line gradually to avoid sudden wave changes, and keep wrist angle below 15° to minimize line slack.
⚠ Common Mistakes
  1. Neglecting visibility during night work risks being cut by hairtail teeth.
  2. If the line is set too lightly, it slips underwater, leading to significant loss.
  3. Excessively increasing tackle weight can overload the line and cause a spring‑back effect.

04Safety Points and Pre‑Trip Checklist

For night outings, always wear a light and headlamp, and use durable protective gloves (minimum 2 mm thickness) to guard against hairtail teeth.

On the boat, place a waterproof mat on the slippery deck and wear a life jacket to prepare for sudden wave changes around tide; if wave height exceeds 1.5 m, have a spare buoy ready for safety.

Before heading out, check the Korea Meteorological Administration marine forecast and Ministry of Oceans and Fisheries notices for wind direction (eastern or southern winds) and wave predictions, and download the local current chart to understand water flow in advance.

“Matching tide and water temperature precisely is the key to hairtail tackle success,” – a veteran angler with 10 years of field experience