Cone snail

[Coridella Starbough]

I'm assuming you don't know what species you've got. I suggest sending a photo to your local museum and asking if they can help with identification (that what I did with my Cone snail shells). Anyway, have a look at the front opening of the shell. If it's wide, your Cone snail is a fish-eater. If it's narrow, the diet is more likely to be either worms or other snails.

 

[Culcita novaeguineae]

where to buy the piscivores, in indonesia is sooo hard near impossible to find one