This achievement will take maybe 3 minutes of actual fishing to accomplish, but it does require a minor amount of time to set up.
First, get 500 standing with the Ostrons. This can be done by doing a low-level bounty from Konzu.
Next, go talk to Hai-Luk. Remember that you can fast travel by hitting
and using the "Fast Travel" menu to travel instantly to Hai-Luk.
Purchase a Fishing Spear
for 500 standing. Equip the spear using the Gear menu (
-> Arsenal -> Gear, at the bottom). Now, go out into the plains.
Near Cetus's gate are a few small lakes. Using this map -
I had success at the lake located at D7. The Grineer nearby are very low level and can be picked off quickly. Once secured, jump to the rock in the middle of the lake and equip your fishing spear (
-> whatever radial you set your spear to).
When you have your spear equipped the ambient noise of the game will soften so you can hear the splashy sound of nearby fish. But, you will also be able to clearly see the fish swimming around the water. Lead your shot accordingly and use
to aim and
to throw your spear. All it takes is one hit to catch a fish. Rotate around the rock and capture fish until you have your ten. A progress meter will pop up with each catch so you know how you're doing.