So last night I heard a thud, which I'm used to hearing between the black wolf and odoe in the bigger tank, I didn't think anything of it but woke up to a dead del, everyone else is fine, he's not in a tank with anything aggressive, just did a water change. That's my only guess. Was a full 9"
I had a del at 14" (yes I know unheard of...) and he just up and died on me too...I didn't audibly hear a crash but my assumption was he domed himself on the side of the tank. sorry for the loss brah.
Sorry for your loss My del goes nuts whenever any of the fish spook it and rams into the aquarium. One day it slammed itself into the side of the glass so hard I thought his spine was damaged.
Good reminder for us all. We get so used to the splashes and noises of our tanks and fish we stop looking to see if there is something going on. I do that too. So sorry you lost your del.
Sorry for your loss. Sometimes when a poly is about to go or experiencing unknown issues. I've also discovered that they will struggle swimming around and bang against the top lid.
Awe man that sucks.. Out of curiosity, is the room completely dark at night? I actually keep night-lights at outlets near all my tanks to reduce the chances of freak-outs.