Why are snails placed in aquarium?

Snails are not typically placed in aquariums for the same reasons you'd add fish or plants. They're not considered a primary "resident" of an aquarium, but rather, they often serve as a beneficial addition:

1. Algae Control: Snails are excellent algae eaters, particularly those that grow on the glass, plants, and decorations. This helps keep the tank clean and aesthetically pleasing.

2. Waste Decomposition: Some snails are decomposers and help break down waste and debris that accumulates in the tank. This can improve water quality and reduce the need for frequent cleaning.

3. "Natural" Ecosystem: Adding snails can help create a more biologically diverse and balanced ecosystem in the aquarium, similar to a natural environment.

4. Aesthetic Appeal: Many snail species are quite attractive, with colorful shells and interesting behaviors. They can add a unique dimension to your aquarium's visual appeal.

However, it's crucial to choose the right snail species for your aquarium:

* Compatibility: Some snails may be incompatible with certain fish or plants, or they may overpopulate the tank if not properly managed.

* Size: Make sure the snails are small enough for the aquarium and don't pose a threat to other inhabitants.

* Feeding Habits: While many snails are algae eaters, some may also nibble on plants, requiring careful consideration if you have delicate or expensive plants.

Overall: Snails can be valuable additions to aquariums, but it's essential to research the specific species and ensure they are suitable for your tank's ecosystem and your own preferences.