Trochus snails not moving but still alive ?

So i added 5 trochus snails to my 30g tank on saturday around 11am .. its now technically monday lol 1.30am .. and they are pretty much still in the same spot .. ive pulled a few of them out to check if there dead but there alive .. are they going to kick the bucket or what ? .. if there going to die id much rather just remove them and chuck em to avoid causing an ammonia spike, they were drip acclimated for around 30 min since my salinity was so close to my lfs .. and there is diatoms everywhere for them to eat .. should i leave them or get them out in a day or two ?, im pretty sure they should be cruising around the tank a majority of the time right ?, or is this there usual behaviour .. sucks there not doing anything from what i could gather onl8ne trochus snails are meant to be great at eating algae and can flip themselves over etc