I’ve seen a lot of weird stuff in aquariums…. I mean alot. From candiru (the fish famous for swimming up the urethra and eating the……….. Cookies in the cookie jar) to freshwater sturgeon fish. From 700 dollar true tigrinis catfish, to a 30 dollar gulper catfish, (the customer would feed it Jack Dempseys). And I’ve personally kept some myself. A few years back I had a 120 gallon oddball tank. I only stocked it with rare south American cichlids and fish I knew were subtle gems overlooked in the aquarium hobby, partially because of their size, but mostly because the lack of color.

 
In my 120 i had:
• archocentrus centrarchus or the flier cichlid for those who don’t speak the dead language. Semi aggressive, but didn’t get too large.
• Freshwater stonefish, one of my personal favorites since I would hand deliver his krill everyday and listen to him oink as he snatched it out of my hands and disappeared into his den.
• Juvenile Fire eel, another favorite oddball fish of mine. Whenever I had company over I always made sure to stick my hand in the water and let swim through my fingers.
• Juvenile lungfish, there’s something about their dopey face and careless attitude toward being handled that really stood out to me, almost if it was saying “dude I’m like millions of years worth of evolution, what are you gonna do? Eat me? Yea right!”.
• VERY JUVENILE Red tail catfish… Not one of my proudest decisions, I purchased him for 29.99 at 2 inches long and only had the guy for about 2 months before he decided to eat his fill of rare South American cichlids. But he was cool while he lasted.

 
Of course there are other odd fish that you don’t see in homes to often like ctenopomas, archers, bichirs and gobies, but the absolute weirdest thing I’ve ever seen is rather surprising. I’ll never forget water changing the 200 gallon tank with one full size red belly piranha and a massive school of neons who went with it. The customers theory was that since the piranha was so large, and the neons were so small, it wasn’t worth the effort for the fish to try to catch them. First of all let me say that’s one of the dumbest things I’ve ever heard and i would NEVER….. EVER recommend this unless you have a deep wallet and a love for mass neon genocide. But I hate to say… it worked. At least when I saw it. Who knows maybe the customer was taking weekly trips to restock 200+ neons. Or maybe the customer got lucky. That tank did teach me the valuable lesson that nothing is definite when it comes to fish.