why did my HY511 runt die?

[Rey]

I saw some of these HY511 hybrid "candy cane" Tetras in the LFS they had been there for months and I noticed one had some defect as he was swimming kind of at a sideways angle. I decided to purchase the whole tank full of about 7 or 8 of them I put them in a Q tank for about a month and then in my 125 gallon but today I discovered my "runt" dead this afternoon . He was was more alpha in that I noticed him grabbing food fast before others and being in otherwise good health despite that he had a bulge on his side and swam at an angle. Well after looking at his body the bottom had ruptured but I am not sure if this was from the gasses after he died or that he had worms? or he was overfed? dropsy? but after looking a bit inside a bit (I was squeamish to autopsy him since I was still sad that he had died)he had been in the 125 gallon for over a month now but I saw no red worms or anything from him.

just curious if this was something I should have de-wormed him for?

He always seemed to have an unusual shape from the others I thought he was just born that way.

 

[Tasha]

Im only assuming that what killed him was the same as whatever caused him to have the bump on his side and swim funny.... sorry for you loss.