Snails are the quiet workers of a freshwater aquarium. Nerite snails are among the best algae eaters you can buy, and mystery snails clean up leftover food while adding color and personality. Both are peaceful, inexpensive and easy, as long as their few needs are met.
| Nerite size | About 1 inch |
|---|---|
| Mystery snail size | Up to about 2 inches |
| Temperature | 72–80°F |
| pH | 7.0–8.0 (hard water protects their shells) |
| Lifespan | 1–2 years (mystery), 1–3 years (nerite) |
| Temperament | Peaceful |
Nerite snails
Zebra and tiger nerites graze film algae off glass, rocks, wood and plant leaves without harming plants. Their biggest advantage: they won't overrun your tank. Nerites lay small white eggs on hard surfaces, but the eggs need brackish water to hatch, so the population stays the same.
Mystery snails
Mystery snails come in gold, blue, ivory, black and more. They eat leftover food, soft algae and decaying plant matter, and they love blanched vegetables. They lay pink clutches of eggs above the waterline. If you don't want babies, simply remove the clutch.
Water and shells
Snails build their shells from calcium. In soft or acidic water, shells can thin, pit or crack. Keep pH around 7 or higher, keep some hardness (GH), and add a calcium source such as crushed coral in the filter if your tap water is very soft. Like all invertebrates, snails are harmed by copper, so check medication labels.
Feeding
In a tank with algae, nerites may not need extra food. If the glass is spotless or the snail is new, offer algae wafers or blanched zucchini a few times a week. Mystery snails need more: sinking pellets, wafers and vegetables two to three times a week.
Good and bad tankmates
- Great with: peaceful community fish, shrimp, corydoras, bettas and most plecos
- Avoid: pufferfish, loaches that hunt snails, large cichlids, crayfish and assassin snails
Is my snail dead or sleeping?
Snails often rest for a day or two, sometimes upside down or floating. A sleeping snail closes its trapdoor (operculum) when touched. A dead snail has a strong, unmistakable smell and the body may hang loosely from the shell. Remove dead snails quickly, as they foul the water fast.
Frequently asked questions
Will nerite snails take over my tank?
No. Their eggs need brackish water to hatch, so they cannot breed in a freshwater aquarium.
Why does my nerite snail keep climbing out?
Nerites explore, especially when new or when water quality drops. Use a lid and check ammonia and nitrite.
Do mystery snails eat live plants?
They prefer soft algae, leftovers and dying leaves. Well-fed mystery snails rarely damage healthy plants.
How many snails can I add?
Start with one nerite per 5 gallons for algae control, then adjust based on how much algae you have.
Shop for this guide
- Zebra Nerite Snail
- Tiger Nerite Snail
- Mystery Snail (assorted colors)
- All freshwater snails
- Algae wafers and sinking food
Questions? Call us at 786-642-3001 or visit the store at 8338 West State Road 84, Davie, FL (Wednesday to Sunday, 12–7 p.m.).