How do Ramshead Snails die, scavenge their own?

[Linwood]

Yesterday I noticed two ramshorn snails that were upside own. One was small and I could not see much, the other I could clearly see the snail body inside, not moving.

Figured he had fallen and would eventually move.

This morning I looked again, the first small one still no motion, I retrieved it and it was a completely empty shell (quite pretty actually, very translucent). Snail organics completely, totally gone.

The other was overwhealmed by about 5 other Ramshorns, like either a mating or feeding frenzy. I suspect the latter.

I just left it alone to see. There's maybe 10 snails in the tank, so it's unusual I think for two to die at the same time, but the others look healthy and happy (as do the rest of the inhabitants). Normal water chemistry, though I did just do an (infrequent) water change the same day these died (I let nitrates get to maybe 40 or so, then do a water change -- it's a planted tank so the nitrates grow slowly).

RODI water, remineralized to dGH=5 or so, dKH=7 or so (a bit higher, it never quite comes out on target), ph 7.6.

I'm less curious what killed them (well, until there are more), than where the body went -- do snails scavenge their own?

Or could one of the fish have done it (congo tetra, serpae tetra, raphael catfish and BN pleco). I assume the catfish will eat most anything but doubt he would leave the shell? The shell is perfect looking, not crushed or anything.

My guess is they died, and the other snails ate the body?

 

[Fishfur]

Very likely you are correct. Snails are, like most shrimp, simply scavengers. They're pretty efficient at cleaning up almost anything, and that includes their own dead. I am not sure of the average life span of the common ramshorn, but it's by no means unusual to see an empty shell or a dead snail being cleaned up by other snails. Unless you suddenly see a number of dead snails all at once, chances are it's just the vagaries of life or age that causes a given snail to pass on.

I leave some of the more attractive shells in tanks until they are fully cleaned, so I can use them for decoration or even jewellery in some cases. MTS [ Malaysian Trumpet] are very, very good at cleaning out the narrow interior channels of many snail species, their own included. Once a shell is emptied out, it will, over time, slowly dissolve into the water until it pretty much vanishes. Older shells may just crumble if you try to pick them up.

Ramshorns are reasonably tolerant of some changes in their water, so long as it's not a big ammonia or nitrite spike, to which they're as susceptible as most creatures. Unlike, say, Mystery snails, ramshorns don't have an operculum, [ a door ] to close to protect themselves, so if they are damaged or a predator gets hold of their foot, they often won't last long.

If water is acidic, their shells will dissolve, which is fatal, though not right away. So, like anything with a carbonate shell, they need adequate water hardness and pH at least at 7, higher is usually better. Your water params are fine for most of the common snails.

 

[Linwood]

Thanks.