The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
I believe I found a sundial snail in my tank. I removed it and took this picture. If anyone thinks this is a mistaken identity, let me know before he's toast.
Here is what I think of when I hear sundial snail, I've never seen one like what you have there. http://www.austmus.gov.au/invertebrates/mal/gallery/philipp.htm
But, the shape of it looks very much like the welks/tulip type snails so I have no doubt it's predatory. Great scavenger/cleanup but not to be trusted with other inverts.
How big do welks get? I had one before and it was identified here and removed. The reason I ask is that I was at a LFS and there was a snail that looked like a welk that was a little over 1.5" in size and appeared to be eating an astea snail. Just curious.
They can grow huge. Around cape cod I used to dig up 8-10" welk shells. It all depends on species though but I wouldn't expect much in the way of small species because of the size of the ones I have seen.
I do believe that is a welk. I had some a while back and found a picture on google of a welk vs. nass and the welks have a dominate leopard pattern. From the snout on that snail it looks like a welk. They do come in all sizes ... the ones I had were about the size of a pencile eraser!