Lumi Shares: My Home Grows Along With Me

Hello, I’m Lumi! My friends often say I’m slow. That’s okay, I like to enjoy the journey. While we stroll along slowly, let’s get to know the secrets of water snails. 🐌

The shell is part of the body, not a rented home

• A snail’s shell can’t come off. My body makes it myself, using a layer called the mantle that keeps adding lime (calcium carbonate) to the lip of the shell.
• That’s why my shell grows bigger as I grow. The fine lines on its surface are growth marks, a little like the rings in a tree trunk.
• The ones who swap shells are hermit crabs. Hermit crabs aren’t snails at all, they’re relatives of crabs like Kori!

A tongue with thousands of teeth

Snails have a radula, a ribbon-like tongue covered in rows of tiny teeth, hundreds to thousands of them. We use it to scrape films of algae off rocks, leaves, or aquarium glass. Worn-out teeth at the front keep getting replaced by new ones from the back. Handy, right?

Some breathe with lungs!

Not all water snails are the same:

• Some breathe with gills and have an operculum, a little trapdoor that seals the shell when danger comes.
• Others, like pond snails and ramshorn snails, have a simple lung and come up to the surface now and then to take a breath of air.

Pond snails can even glide upside down under the water’s surface, sliding along their own slime. Like taking a walk on the ceiling! 🙃

The pond’s cleaning crew

Many water snails eat algae, rotting leaves, and leftover food, so we’re often called the cleaning crew of ponds and aquariums. If the number of snails suddenly explodes, it’s usually a sign there’s too much leftover food in the water.

Our shells also need clean water with enough minerals. Water that’s too acidic can make shells brittle. So when you keep water clean, you’re looking after our homes too. Thank you! 💙

Going slowly still gets you there. What matters is to keep moving. You’ve got this today!