"Having only coordinates guarantees a catch" is a lie
Beginners in artificial‑reef fishing often ask the most common question: "Please give me the coordinates." In fact, coordinates are just a starting point. Even when you go to the same coordinates, some anglers return with a full cooler while others come back empty because the artificial reef is "how to read it" different for this reason.
Since 1971, the Ministry of Oceans and Fisheries has maintained an artificial reef program, resulting in tens of thousands of reefs installed along our coastlines. Evaluations by the National Institute of Fisheries Science consistently show that catches around artificial reefs are significantly higher than in open waters. The issue lies in precisely the technique of stopping precisely.
01Read simultaneously with three tools
Artificial reef interpretation cannot be completed with a single tool. Artificial Reef DB·Nautical Chart·Fish‑school Detector Overlay the three readings, and add current as a variable, only then can the condition of "that reef on that day" be seen. This is because each tool provides information with a different texture.
02First tool — Ministry of Oceans and Fisheries artificial reef DB
Artificial reef data managed by the Ministry of Oceans and Fisheries and local governments includes coordinates, installation year, reef type (square, hemispherical, forced reef, etc.) and depth. Artificial reefs are preferred species vary by type. Even for the same "artificial reef point," the rig and bait must be completely different depending on the reef type.
03Second tool – nautical chart
The Korea Hydrographic and Oceanographic Agency nautical chart shows not only the precise location of artificial reefs but also the surrounding seabed topography is displayed. The value of an artificial reef lies not in the reef itself but "artificial reef + surrounding topography" comes from their combination.
- lonely artificial reef on a sandy bottom: single point, high species concentration
- artificial reef at the edge of a rock wall: artificial reef + natural structure combination, golden point
- deep seabed valley combined with artificial reef: maximizes current shielding effect
When viewing the nautical chart observe how the isobath (line connecting equal depths) bends around the artificial reef We look at that. When isobaths converge tightly around a reef, the area is steep and an excellent spot for bait accumulation.
04Third tool — fish school detector / sonar
It's the most real‑time tool. When viewing the fish‑school detector over an artificial reef, there are three signals you need to check.
- The “pillar” or “wall” above the bottom signal: the main body of the artificial‑reef structure
- The “cloud” signal 5–10 m above it: a school of baitfish
- Thick dots between the bait: predator species
The moment all three signals are detected simultaneously is the timing to start casting and descent. If there is only a pillar and no cloud, that artificial reef is likely inactive that day. It’s more efficient to move to the next reef rather than waste time.
05Fourth factor — current
According to the Korea Maritime Institute’s current data, even the same artificial reef the location where fish species settle varies with current direction changes.
- Current‑facing side (front face): the side where bait strikes. Area of highly active predators.
- Current‑downstream side (rear eddy zone): the side where larger individuals stay to conserve energy.
- Current pause (slack tide): fish are dispersed across the whole reef. Bite is weak.
When the current is strong, the artificial reef front 5–10 m drop the rig and let it drift, and when the current is weak, the artificial reef directly above is standard to drop it vertically.
06Practical – five steps to stop over the reef
- DB·nautical chart pre-select 3–5 candidate artificial reefs
- GPS·plotter first entry, do not enter within 20 m radius of reef coordinates
- Confirm signal with fish‑school detector, stop when bait and predator signals are detected simultaneously
- Determine current direction, adjust anchor or stop (spool lock) position to the front of the reef
- Concentrate on the vertical zone of only 1–2 m, move within 30 minutes if signal breaks
- Do not stay on the pillar alone— If only structure signal (pillar) and no bait cloud, the site is inactive that day. Move on to the next reef without hesitation.
- Do not drop directly onto the coordinates— When current is strong, drift 5–10 m in front of the reef. Vertical drop directly above only when current is weak.
- Do not linger too long on a single reef— Move within 30 minutes if signal breaks. Cast a wide net for candidates and keep stay time short.
07If you remember only one thing
The core of reef fishing is “cast wide and stop narrow.” Depart with many candidates, but stay briefly and precisely at locations showing activity that day.
This is the biggest difference between veterans and beginners.