Sorry this is long. I wanted to include every detail. -- Last week I did my water change and couldn't find my two nerite snails. That's not unusual as they're typically hanging out behind the filters or deep inside a decoration. But this time my zebra nerite never came out of hiding. I looked for him everywhere, inside and outside of the tank. After 5 days I asked my brother to check the filters for me since he's much taller than I am. And that's when we spotted the poor guy. He was indeed outside of the tank on a little windowsill! Now I really can't tell if he's still alive He was right side up when we found him, and if he escaped during the water change (I'm assuming, because the tank has a lid and every opening is taped shut) then he was out of the water for 5 days. He looks to be sealed inside his shell completely all the way around. From what I've read online they smell awful when they're dead, but he didn't smell at all that first day. And I've read that they fall out of their shell when they're dead but he's stuck in there pretty good. I had him in a cup of water with an algae wafer the first night but worried about temperature fluctuations and ammonia building up, so since he didn't smell I put him back inside the tank. The corycats seem overly interested in him, which has me concerned so I smelled him again today and he smells a bit more like poop, but still not anything cringe inducing. His body is still pink but the edge that touches the shell is grey, which I think is how he's always looked. These are the best pictures I could get How can I tell if he's still alive? He definitely hasn't moved and it's been two days. Is it possible he could be hibernating? Could he really survive for 5 days without food? If he is dead, how quickly would that foul up the tank water? I don't want to put my other fish at risk. He's still in the tank surrounded by plants so the cories can't mess with him.