ok i have a GSP and he is freaking awesome, but i need snails that will live in brackish water. the snails i put in his tank now, some of them die before he eats them. i bought 3 mystery snails, one with a broken shell. will he eat these? they are quite big, as big as him, he is only about 1 1/2" long, but i want his teeth to be keep grinded down. any help please