Weird snail situation
Hi I have 25 gallon tank (only had around 6 months) I had an aquatic snail in there with platys and tetras.
Last week I noticed the shell had not moved for a few days and was lodged in a plant. I gave it another day then removed it as it looked empty.
Nothing in the shell no snail, so I disposed of it. 2 days later I find what appears to be tiny snail (looks like the head) alive and attached to side of tank.
This was about 4 days ago and it's still alive, but now I've found another small what looks like a snail that is alive! I'm confused.
I've read they are not supposed to live outside the shell. I'm struggling to understand whats going on and what I should do about it (if anything).