I found some pest snails in Pokas tank (forgot to de-snail the plants >_<) I plan on keeping them with my other pest snails that Smack sent me (only one is left) I found some odd ones. thier pointy. well, triangular. the shell is cone shaped. its hard to explain. anyone have any idea what kind they are?

odd part is, sometimes they go above the water, like they need air.