Hello again,
I made what everybody had said, and i think that's working.
i'll wait a little to see what's happen...
later i tell if everything goes ok.

ont remercié tout le monde (acho que tá escrito tudo errado, alguém fala português?)

thank's

Hello again
JTanganY now i'll put some smaller shells.
Henry, i have shells in more than 4 places(quiet places), eich place with more than 6 shells, but i'll try that.
P. thanks

Thanks everybody

Hello! I'm from Brazil and my english is very bad and my french is worse. Ok, i have 3 n. brevis "Zaire", 3 n. multifasciatus, 4 l. ocellatus, in a tank(250L) i put 30 shells, big and small, but nobody go into the shell, they're only stay in the rock's, why? and, how i know which one is fe...