Had turbo snails about a week half now tryed to put them off as long as i could due to personal chocie but now i have them i think there great a real 10 of 10 on the cleaning of my glass etc but cause for concern a little i have a fixed lid on my tank witch is the filter&light`s but every so often a snail will slither up the side of the filter pipe are glass to the very top then go out of the water on the bottom of my fixed lid is this normal for these snail to slither there way out of water? what should i do knock them back in are just leave em to it ? CRAZY 