Glass Bloodfin Tetras

Are you sure they killed it, and didn't just take advantage of an already dead/dying fish?
 
First Rule of Fish: If it's not getting away and can be eaten, it's food.
Second Rule of Fish: If it's edible, eat it.
Third Rule of Fish: Everything is edible.

If the pleco was already dying/dead then pretty much any fish would eat it, if it was healthy and active then that scares me... I've always found plecos to be the more durable of my fish species.
 
Sounds to me that the pleco just died, and the other fish took advantage of a fresh seafood buffet. Plecos are pretty tough, and usually the worst you hear is that they lose an eye to some kinda cichild.
 
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