Who Gives A Fish Forums

Ugh, it's happened again. I just brought home another betta that was stuck in awful conditions - he just caught my eye, you know? So, to be clear, he's in QT for now. When I first saw him, he seemed okay aside from being starving and swimming in gross water, but when I put him in my 5gl QT tank, I noticed this bend and my mind immediately went to the worst-case scenario. Honestly, I think it was just how he was positioned, 'cause in other pics, it's barely noticeable, but in that one, it's super obvious. I need some opinions - am I just freaking out? I'm terrified I've introduced some horrible disease into my fish room, even with him in QT, it's still scary. I'm trying to calm myself down 'cause he's active, no sores or fin/scale damage, just really skinny, which, let's be real, there was literally no food in that tank, just waste. Now, I don't even notice the bend, but still...

Here's another photo where I'm seeing that S curve - I'm really trying to get a better look at it to see if it's my imagination or if it's something more.

Honestly, I've been around fish for a long time and I've never come across Fish TB, it's super rare. I'm pretty sure your guy's just struggling from being malnourished or dealing with some water quality issues, that's my two cents.