What they eat
- Soft algae on glass and hardscape
- Biofilm on mature surfaces
- Small pieces of uneaten food
- Dead or damaged plant tissue
What they cannot do
They do not remove nitrate, perform water changes or reliably eliminate hard algae. They also cannot correct overfeeding or an uncycled aquarium.
Are they safe for plants?
Healthy bladder snails usually prefer biofilm and soft decaying material. They may be seen on damaged leaves because that tissue is easier to graze; this can look like they caused the original damage.
Using them responsibly
Keep a balanced number, feed the aquarium appropriately and continue normal maintenance. A sudden increase is a useful warning that extra food is available.
Think of bladder snails as recyclers and indicators—not a complete cleaning service.