mystery snail shell going white and chalky?? am i doing something wrong

[FreshwaterFan]

so my mystery snail (had him about 5 months) has this patch on his shell that's gone pale and kind of chalky? and the edge near the opening is getting thin, like i can almost see through it a little. idk if that's just new growth or if something is actually wrong. i'm worried.

tank is a 10 gal, 78F, ph around 7.4 i think. ive never once tested gh or kh. didn't even know that was a thing until last week lol. i feed him algae wafers and sometimes blanched zucchini. is he not getting enough calcium?? do i need to drop a cuttlebone in there? i keep seeing people say cuttlebone but won't that mess with my water params? i have shrimp in that tank too and i really don't wanna hurt them while trying to help the snail.

im probably overthinking this but he's my favorite and i do not want him to die. also kinda random but i was gonna get a dwarf crayfish to deal with the algae instead and then i read dwarf crayfish and shrimp compatibility and noped out of that real fast lol. so snail it is.

anyway, is the white shell thing reversible or is that permanent damage once it happens? and how much cuttlebone do you actually use for a 10 gallon? like a whole piece or just a chunk?

[ChrisM_22]

The chalky patch is almost certainly calcium loss, and yeah, once it goes white like that it doesn't really "heal" back to normal color. The snail will lay new shell over the thin spots eventually but the pale patch stays pale. So don't panic, it's not an instant death sentence, but you do need to fix the water or it'll keep getting worse.

Cuttlebone is the move. A whole piece is way too much for a 10 gal, just break off a chunk about the size of a quarter and let it float or wedge it near the filter outflow. It'll slowly dissolve and buffer your GH. Your shrimp will actually benefit from it too, they need the calcium for molts just like the snail does. Won't crash your params unless you dump like half a bone in there. Test GH/KH though, seriously. You can get a liquid test kit for like 12 bucks and it'll tell you if you're at 3 dGH or 12. That number matters more than the pH for shell health.

And yeah good call on the dwarf crayfish. Those things are little murder machines. I had one years ago that wiped out a colony of cherry shrimp in like 3 days, didn't even eat them all, just killed for sport it seemed like. Snail is the safer bet for algae anyway, they graze constantly instead of ambushing stuff.

What's your KH sitting at? If it's super low you might be fighting a losing battle just with cuttlebone and need to look at your water source.