I have a pristella tetra that has an unknown cause for his swimming habit. I am wondering if anyone can tell me what may be causing him to swim or do the jig as it seems. He is always tail down nose up. He seems to be eating fine and does not have any other problems that I know of. I have had him since he was a baby, I got him with some other baby fish from a lfs, and he has always done this (as long as I can remember). Just curious what could cause this. The tank has been set up for years and everyone else in the tank is healthy and happy. Will try to post a vid if I can figure out how to. So I can not post a video so here are a couple of pics of the fish in question.
Sorry for the quality of the pics were taken with my phone.
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