I kept one for over two years in a 29g, when I moved everything to a 65g it didn't survive. I had some serious water chemistry problems! That was a learning experience. The stock in the hobby now-a-days seems weak.
I bought one, and a week later it died, it looked fine, but the night before, he was at the bottom of the tank n a sideways position, not completely sideways, but kind of tilted, he was floating the next day