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The cane
Although the arapaïma is a fish that can reach impressive dimensions, it can be fished with relatively light tackle compared to its size. I've been known to successfully fight fish weighing around 40 kg with a 9' #9 rod. However, for larger fish (150-200 kg), a good 12' rod is imperative. To gain in responsiveness, it's important to have a fast-action rod. As a general rule, the time you have before making a cast is relatively short.
The reel
A wide arbor reel with a good drag is a must. Although the arapaïma is not a fish that makes big rushes, big fish can take you quite easily on the backing. In this case, stopping a big arapaïma by grabbing the backing with your hand is almost impossible, if not dangerous for your fingers. The drag is therefore very important and must be able to withstand a prolonged stay in the jungle, a particularly aggressive environment for the equipment (extreme heat, humidity, sand, dust, etc.).
Silk
A WF (weight forward) line with a short spindle allows you to make fast, accurate and distant casts with very few false casts. Arapaïma fishing requires fast and accurate casts. In general, you need to land the streamer within a metre of the fish's head, before it moves, and sometimes (often) more than 20 m away. It's also important to add about 100 m of backing in 40-50 lbs to the line.
A 30-lb fluorocarbon leader is sufficient. I also add about 30 cm of 30-lb sheathed steel. The arapaïma doesn't have particularly sharp teeth, but the places where I fish are infested with piranhas. These fish have powerful jaws capable of cutting any non-steel line. My tippet + leader measures the length of my rod. This is more than enough for discretion and allows me to make fast, accurate casts.
Flies
There's nothing complicated about flies. Unleaded streamers with a gliding action are perfect. I like to use Gamakatsu SL12S hooks in 6/0 or 8/0, or Tiemco 600SP in 3/0.
Personal equipment
Pants and a long-sleeved shirt or t-shirt will protect you from the sun and insect bites. A cap and sunglasses will complete this protection. Rain gear is also advisable, as is an overnight jacket. Don't forget that you're in the middle of the jungle, far from the nearest town. So it's essential to pack an appropriate first-aid kit. Don't forget antihistamines, as insect bites can quickly become unbearable.
