Few weeks ago I got a piece of plant from a wild pond and put it in a jar to watch it grow and see if it would look good in my pond. (Anacharis I think) I took a net to my pond and found a trapdoor snail to put in the jar to clean the plant. After a while I put a second in. Today I looked in the jar and see about 24 tiny snails crusing around. Do trapdoors have that many in one shot? I know mine have had babies in the pond but didn't know that many at a time. They are too small to really identify yet but I didn't see anything on the plants that would be snail eggs so I'm pretty sure they are trapdoors. I may have to rehome these little guys.