snails shell question

my pleco sucks on the snails and clams i think once the shells are damaged like tom says they start to dissolve the calcium in the shell goes from a higher concentration (the shell) to a lower one (the water) I havent tried adding calcium but have heard of people putting a little crushed coral in the filter . I belive this would be done to change water chemistry and not to help clams or snails.

 

Do you happen to know the calcuim content of your water? There are certain area here in the US that have problems with snails because of mineral content of the water.
People with low calcium in their water have added cuttlebone to their tanks for their snails to graze on. It's usualy something given birds to chew on for their diet. It will help some, but not entirely make up for lack of calcuim in the water column.

When you observe the live snails in your tank, do their shells show small holes or flakes? This may mean they are not getting enough calcuim either in water or diet.

 

I always have snail issues unless I dose Ca. Not just pitted shells, but the whole shell going white and brittle, ultimately causing death. I've tried on several occasions to go without dosing Ca but the end result is always the same. In my CO2 injected tank the effects are very quick (about a week) but take longer in non CO2 tanks.

 

Everyone I know here in Columbus has trouble with snail shell erosion. I've looked at the water report but there's nothing unusual. It's kind of annoying because I really like the critters in my tank. If I drop Ca, they start dying off. It would be a big coincidence that suddenly something damaged their shells everytime I lower Ca.

I'm open to suggestions. It would be a huge breakthrough to figure this out.

 

Don't you even have problems with them reproducing, Reiverix? Or are they just not living long enough to do that?

 

I can keep a steady population if Ca is above ~60ppm. I've been thinking about some high calcium snail food recipes and see if that helps.

 

I'm pretty sure it's a pH thing. Snail shells are composed of CaCO3 like everyone else said, which dissolves into the water at a low enough pH. When I started my tank, I aimed for the KH ~ 4 and pH ~6.8 to get a good CO2 level and my ramshorns' (which seem to be more sensitive than some other species) shells all started taking on a white pitted appearance. I've since taken to adding some baking soda during WCs to raise pH above 7 and still maintain a good CO2 level, and while the old holes in the shells haven't healed, new ones haven't developed either.

 

A PH of lower than 7 can corode snail shells really fast. They really dont like acidic water. If your adding CO2 then its likely that your PH is going to drop below safe levels.

 

If I recall correctly, snail shells are not primarily calcium carbonate. They are, I think, mostly a protein. Most of us using CO2 with low KH have a pH below 7, without problems with snails, other than having far too many.

 

Interesting, this is something that Ive read in 2 separate places now, both on snail/invert supplier website. Im wondering if theyre just over-covering their backsides?

 

snail shell composition

That does not sound completely accurate.
My understanding is that the snail shell is primarily composed of calcium carbonate but that there is a protective outer covering.
The outer covering of the snail shell is the periostracum, which is mostly protein.
Drop the snail shell in acetic acid and the dissolving calcium carbonate will form bubbles of CO2 as it dissolves.