Medium tackle with a steel leader. Careful unhooking: the teeth cut.

The gear must measure up to a strong fish that runs, jumps, and lives in current with structure. Specific recommendation:

Spinning (standard setup)

• Rod: spinning rod of 1.80 to 2.10 m, medium to medium-fast action and medium / medium-heavy power, with a good response for setting the hook in a hard mouth.
• Reel: a sturdy spinning reel size 3000 to 4000, with a progressive, reliable drag to hold up to the runs.
• Line: braided line of 20 to 30 lb; it gives sensitivity, low stretch for a solid hookset, and the load capacity for big fish.
• Leader: an anti-cut leader is essential because of the teeth: thin flexible steel (coated steel cable) or heavy fluorocarbon of 40-60 lb. Without it, the dorado cuts the line with a single bite.

For trophy specimens or big rivers: step up to a medium-heavy/heavy rod, a 4000-5000 reel, and 30-40 lb braid, with a steel leader.

Fly fishing

• Rod: #8 to #10, fast, to move large streamers and fight in current.
• Reel: with a good disc drag and backing capacity.
• Line: WF (weight forward) matched to the rod number; in fast water a sinking tip may be advisable.
• Tippet / leader: finish with an anti-cut section of steel or heavy fluorocarbon, just as in spinning.

Key accessories: strong, well-sharpened hooks (ideally barbless if you're going to release), long pliers to unhook without hurting yourself on the teeth, and if you practice catch and release, a knotless/rubber net and gloves to handle the fish carefully.