Can the pygmy be nocked out by the water flow?
Hi everyone. New aquarium and cory owner here. I have so many questions, but the one that made me write this post is in the headline. (Photo before the incident, just because it is cute).
One minute I saw my pygmy cory perfectly normal and the next minute his lifeless body was moved by the flow, and dropped to the ground where he stayed, belly up for a while.
Eventually he straightened up, but remains in the corner kind of stunned. Is he going to be ok? Should I look for some other danger apart from the water flow?
Some context: I set up an aquarium with plants at the beginning of the year, and 3 weeks ago I bought online amano shrimps, 20 cardinal tetras and 10 pygmy corys. All the tetras and shrimps are doing great, the corys on the other hand arrived very weak, 3 of them were dead, and the rest but one likely died in the week after. I only saw 2 bodies, but basically there is only one visible cory left. He seems to be rather content, hanging out on the leaves in the middle of the aquarium, surrounded by his adopted neon siblings. I call him Mowgli.
Water values are stable. I caught and removed the highly developed dragonfly nymph the first week after the fish arrived(my best guess - it got in earlier with the plants and sustained itself with the baby snails), not sure if there can be more.