Oto with a really chubby belly

After spending some more time looking at them, they definitely don't seem to have the suckermouth thing going on. My guess is raspboras.
 
Sorry to hear that Lunchbox. It's hard to say whether or not the fat belly was related to it's death or not, without doing an autopsy. From the pics I don't see any redness that would indicate an infection, and it sure looked like a gravid female to me. I wonder if internal parasites may have been the cause. In any case, it's not uncommon for otos to die within the first few weeks. I've had pretty good luck with my stock, but it seems like it's usually a gamble.

Again, sorry to hear about it - I was really hoping you'd end up with some fry!
 
yeah me too... not sure what exactly it was but my guess right now is an internal parasite or infection. I think if it had shown some spawning behavior (like was described on that one link I put in here) I might be more inclined to think it had a bunch of eggs and died for another reason, but there was no spawning type behavior really.
 
AquariaCentral.com