What happened?

[tenxiong]

I had an arowana a few months ago, it was about 4 inches and still growing. I was feeding it meal worms and it was very active and really healthy. Then one day it suddenly died, it had no scars, no fungus, no ick, no nothing. I woke up one morning and found it swiming verticaly. I was wondering if you guys had an idea what might had happened?

 

[Andyplec]

Well im not sure its the same with fish, as it is for reptiles, but if a mealworm is swallowed live, it will start to eat its way back out, and may have damaged the swim bladder from the inside of the arowana! I'm unsure, so its just a suggestion!