Why didn't you put him in the tank to begin with? As long as he's in the tank and has vegetable matter such as the cucumber, he'll be fine. Anyways, you know they're dead when their trapdoor is loose. Pick him up, turn him over onto his back, and poke the trapdoor. If it closes tight or is already closed tight, he's alive. Nerites take a bit to get moving, but they're reluctant to get off of a surface after they attach to it. Also, they glide smoothly around the tank once they get going. They're very active!
Also, being in the jar is bad for him. There might be temperature fluctuations and then there's nothing for him to eat. At least if the nerite is in the tank, there's microscoping things for it to eat or algae that you don't see. They eat diatoms like otos, so it's better to put him in the tank.
100g Native Fish Pond, 55g Goldfish/Catfish Community, 50g Plant Pond, 40gB Tetra/Cory Community, 20gHM Community, 20gH Turtle (Bender [RES]), 20gL Turtle (Kif [YBS]), 15g Reef, 5.5g Betta (Okami), 5gFBH Betta (Pron), 5gHex Betta (Twister)
2 dogs, 13 cats, 2 turtles, 1 bearded dragon and 1 crested gecko
Last edited by Kiara1125; 07-21-2013 at 01:48 PM.