Morsie, I have never had the opportunity to fish for Amazon Peacock bass, but my flies have made several successful trips, and as Dan says, jig hook flies are the way to go.
First flies I tied for Amazon Peacock bass were 8 inch Spinsters ties on 4/0 EC 413 jig hooks, more than 20 years ago, before the newer 60 degree bend jig hooks became popular. So if you still have any EC413â€™s around, donâ€™t be afraid to use them - never have a failure reported on Peacock bass.
Last trip my flies made were a couple of years ago by a good friend of ours, who caught five Peacock bass in his first five casts on big 4/0 EC413 Spinsters, Peacocks 17- 22lbs.
I believe most will recognize â€œthe master anglerâ€ in the photo below.
Good luck on your trip.
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