This guide will let you know where to find Ostimyr in Warframe.
Ostimyr only spawns during fass, and they spawn near/in water sources across the above ground/surface of Deimos. They can only spawn in hotspots, so you need to make sure you’re looking for hotspots specifically when searching for the places.
These are some places where you can usually go; the hotspots spawn in the areas that look like mini lakes/ponds.
You will see a glowing, greenish-blue type aura in the water source in the hotspot. You can also use the fass residue to make them come out faster, but you don’t need it to get the fish to spawn.
