Sadly this horror story is my own fault and I'm still deeply ashamed of it...
A few years ago a friend of mine had two pet axolotls. For those who aren't aware axolotls are relatively easy to care for however they do have some very strict care specifications relating to the kind of water you use (standing water), the amount of water changes they need, their diet, temperature and general environment in their tank. Anyway one of their axolotls died and the friend was getting set to move, they already had a tank of snapping turtles to move and her mum wasn't prepared to transport the lotl too, so she was planning on putting it in the freezer so it would die painlessly. I was horrified and paid her for the lotl, tank and equipment.
The thing is I had zero experience with...well any pet, my parents had never allowed them in the house so I was relying on this woman for information. But it seems she didn't do her research because ALL the care instructions she gave me where for the turtles, not the lotl. So when I got her she was already sick and I tried everything that the woman said. It was only later when she got REALLY sick and I did further research that I learned just how harmful the information I had been given was; I was using salt water which was incredibly harmful, the temperature was all wrong, there was no hide in the tank, you name it. I did everything I could to backtrack and make the environment safer but it was too late, Lottie died a couple of days later.
Moral of the story, if you ever get a pet you're unsure about do every bit of research you can BEFORE you start taking care of it. And if someone goes from having two to one before you get the other, they're doing something wrong and do NOT listen to their advice. Still feel really bad about the whole thing to this day, might have saved Lottie if I hadn't listened to the advice of that fucking idiot.