At Least It's a Carp

At Least It's a Carp is a Fishing triumph added in Season 21 (Season of the Deep): catch the fish "At Least It's a Carp". The Destiny 2 Fish List says 200 catches of this fish are needed (unverified in-game).

How to complete

1. Unlock fishing by finishing the Season of the Deep Salvage and Deep Dive missions, then collect the rod from Hawthorne.
2. Fish at the holes at the Outskirts (EDZ), the Cistern (Nessus) and the Miasma (Savathun's Throne World).
3. Cast with interact, and press again the moment the bobber dips. Each cast costs one bait.
4. Use Focused Fishing: groups fishing together raise a meter that improves odds.

It is a rare triumph (about 4% of players).