Snail Problem

[Raven2k]

I am currently having a snail problem. So here's the story.

I have a variety of snails in my tank Nassairus, Trochus, Turbo and Cerith.
Recently, the magority of my snails are either dissapearing or not moving around much. I did some research and I did find what I think are Pyramid snails that could be the problem. However, I have only ever seen them on the turbo snails which haven't moved in days and stay closed up. The cerith snails have been sitting on the sand not moving, not coming out but there have been no signs of pyramid snails on them. I took one out to examine it closer today and I found some flat almost transparent things (about a half dozen of them) crawling on the cerith's shell. i took a picture to see if anyone could identify it (see below). They are about a 1-2mm long.

Are they anything to be worried about? And is there anything else I can do to sort out what the problem with the snails dying out in the tank? So far I have been trying to remove any/all pyramid snails manually, but there really have not been very many that I have seen.



Nitrate, ammonia and nitrite are at 0
SG is 1.025
Phosphates are 0
Alk is at 8.6 dKh as of a couple days ago.
Calcium is at about 380
ph is 8.2