Arapaima are the largest scaled freshwater fish on earth. The fossil record puts their lineage at over 50 million years. They breathe air, reproduce with dedicated parental care, and grow to 200 kg on a diet of fish, insects, and whatever else the Amazon flood plains provide. In Thailand, they are the centrepiece of the finest freshwater pay-lake fishing in the world. This itinerary gives you seven days to catch one — or several.
A single-species week demands that you trust your guide completely. If they say the fish are not on surface lures this morning, switch to floating bread immediately rather than persisting. Arapaima guides at Gillham's have watched these fish for years and their reads are accurate.
Why Thailand for Arapaima?
The Amazon is the arapaima's native range and it offers wild arapaima fishing in remote river systems. Thailand offers something different: managed lakes where fish of 80–150 kg are catchable on a day ticket with an experienced guide, catch-and-release protocols that maintain the population at extraordinary weights, and an infrastructure of accommodation, equipment, and expertise that makes the fishing accessible without sacrificing the experience of fighting genuinely massive fish.
The first time an arapaima rolls at your surface lure — all scales and ancient geometry — is a fishing memory that does not fade.
Gillham's Fishing Resort in Krabi holds the highest concentration of large arapaima available to rod-and-line anglers anywhere on earth. IT Lake Monsters and Exotic Fishing Thailand in Bangkok provide a complementary experience with different lake characters and, importantly, allow comparison of how arapaima behave in different managed environments. This itinerary covers both.
Day 1: Bangkok Acclimatisation at Bungsamran
Landing in Bangkok and going straight to the fishing is the right approach. Bungsamran Lake has held arapaima alongside its famous giant catfish population for many years, and an afternoon session there serves two purposes: jet lag mitigation through active fishing, and the first taste of arapaima behaviour in a Thai pay-lake context.
Bungsamran's arapaima tend to be slightly smaller on average than Gillham's, but there are large fish in the lake. More importantly, the guides at Bungsamran are skilled at explaining arapaima feeding behaviour — how the fish rolls to breathe, how it positions relative to a surface lure, and the crucial moment to strike versus let the fish commit. This contextual knowledge is worth having before Gillham's.
See the Bungsamran Lake venue profile for full details.
Days 2–5: Gillham's Fishing Resort — Four Days of Dedicated Arapaima Fishing
Four days at Gillham's is the right commitment for a serious arapaima campaign. One day gives you an impression. Two days gives you a proper attempt. Four days gives you time to understand the fish, adapt your methods, and specifically target the largest individuals in the lake.
Understanding Arapaima Feeding Modes
Arapaima feeding is not constant. These fish cycle through different behaviours depending on temperature, time of day, light levels, and barometric pressure. A Gillham's guide who has spent years watching the same fish develop an intuitive understanding of these cycles. As an angler, your job is to trust that understanding and execute the presentation.
Surface lure mode (most common at dawn and dusk): The arapaima is actively hunting and will respond to a large popper or walk-the-dog lure crossed within its field of vision. The strike is confident and deliberate — the fish rolls onto the lure rather than attacking from below. Set on the weight, not the strike.
Floating bait mode (common during mid-morning and afternoon): The fish feeds more casually on surface items — floating bread, dead fish presented at the waterline, floating pellets. These takes are gentler and require a slightly longer pause before striking.
Mid-water mode (conditions-dependent): A whole fish on a sliding float at 1–2 metres depth. Some of Gillham's largest arapaima prefer this presentation and take with surprising confidence. The float goes under and the fish moves away — strike after the line comes tight.
Arapaima have bony, reinforced mouths that are difficult to hook reliably. Single inline hooks on surface lures outperform trebles for penetration and hold. Leader of at least 80 lb fluorocarbon is standard — arapaima gill plates and scales can abrade lighter material on a long fight.
The Four-Day Session Structure
Day 2 (arriving Day 2 afternoon): Orientation and first session. Surface lures, let the guide introduce you to the lake's layout and the visible fish.
Day 3: Full day, methods rotation. Morning surface, afternoon float-bait. Work through both presentations and assess which the fish are responding to.
Day 4: Refine on what worked yesterday. If surface was producing, stay with it in the morning and experiment with location. If float-bait was better, do the reverse.
Day 5: Target specific fish. By the third full day the guide will have identified the biggest arapaima that has been showing and will structure the session around putting your bait in front of it.
Compare Gillham's with Bangkok's freshwater options in the Bungsamran vs Gillham's article, and see the Gillham's Fishing Resort venue profile for full details including rates and contacts.
The Arapaima Fight
A large arapaima fight has three phases. The initial run is fast and usually towards the deepest part of the lake — maintain pressure but do not pump hard immediately, as the hook hold needs to establish. The middle phase is a grinding battle of attrition; the fish uses its body like a rudder against the current of its own movement. The final phase, as the fish tires, involves repeated surface rolls where it tries to use its air-breathing behaviour as a fight tactic — keeping the head out of water and rolling. This is the most dangerous moment for hook pull; keep the rod angle low and maintain steady pressure without jerking.
An arapaima roll at boatside — all 100 kg of it, still fighting — is one of freshwater angling's definitive images.
Days 6–7: Bangkok — IT Lake Monsters and Exotic Fishing Thailand
The contrast between Gillham's and Bangkok's specialist exotic lakes is informative. IT Lake Monsters sits in a suburban setting but stocks arapaima that have been growing for years and reach significant weights. The lake is smaller than Gillham's, which means less territory to cover and, on good days, more encounters. The fish can be seen rolling from the bank in the early morning.
IT Lake Monsters allows both bait and lure fishing for arapaima. Their guides can advise on the current most productive method — it changes with the season and with individual fish behaviour. Do not arrive committed to a single method.
Exotic Fishing Thailand offers an alternative venue with its own arapaima stock and character. If your IT Lake Monsters Day 6 session was productive but you want to see how a different water fishes for the same species, Day 7 at Exotic Fishing Thailand provides excellent comparison data.
Both venues are profiled in detail at IT Lake Monsters and Exotic Fishing Thailand.
Arapaima by the Numbers
Understanding what you are targeting contextualises the week:
- Maximum recorded weight: approximately 200 kg (wild Amazon specimens)
- Typical Gillham's catch weight: 40–120 kg
- Air-breathing interval: every 5–15 minutes (varies with activity level)
- Preferred water temperature: 26–32°C (Thai pay-lakes maintain this year-round)
- IUCN status: Data Deficient (A. gigas); listed on CITES Appendix II
Arapaima were once consumed freely in Brazil and are still eaten in some range-state communities. In Thailand they exist exclusively as catch-and-release sport fish. Every fish you catch and release contributes to the ongoing population that makes this fishing possible.
Tackle Reference
Rod: 7'6"–8'0", medium-heavy casting or spinning, 40–80 g lure weight rating
Reel: Robust baitcaster or large spinning reel, 50+ lb braid capacity of 200 m minimum
Main line: 50–65 lb braided
Leader: 80–100 lb fluorocarbon, 1–1.5 m
Lures: Large surface poppers (80–120 mm, 40–80 g), walk-the-dog stickbaits (100–120 mm), floating swimbaits
Bait rigs: Running sinker or float rig with 8/0–10/0 single hook, whole small fish or floating bread
The Arapaima Tackle Guide covers every component in detail. Gillham's and both Bangkok venues supply house rods — bring your own lures and leader material if you have preferences.
What Makes This Week Work
The single-species focus is not about limitation — it is about depth. Seven days on arapaima produces more knowledge about the fish than a month of occasional encounters spread across a mixed-species itinerary. By the final session you will understand how arapaima position in a lake, how they respond to weather changes, how their feeding behaviour shifts across a single day. That understanding is what separates an angler who has caught an arapaima from one who knows how to catch arapaima. This week produces the latter.
