[framerguy]

many (probably all) animals adapt to their environment. A cirith snail that lives in tide pools with naturally have the ability to adjust to changes because they must to survive. A cirith that doesn't come from tidepools will not have that ability. I usually don't know where the animals in my LFS or online were collected, therefore I think I would err on the side of caution and acclimate a long time. If you hand pick your animals from a tidepool, you can pretty much figure they have the ability to adapt, so stand as far as you want from your tank and throw them in. I would like to give my animals the very best chance for survival that I can and if acclimating a long time gives me piece of mind, I'm gonna do it.