30 Frequently Asked Questions about Snails in Freshwater Tanks

30 Frequently Asked Questions about Snails in Freshwater Tanks

Here you can find the answers to some of the most commonly asked questions about snails in freshwater tanks, including questions about health, feeding habits, compatibility, behavior and everything in between.

1. What is a freshwater snail?

Freshwater snails belong to a larger group of shelled animals called mollusks. They are soft-bodied animals that carry with them a protective shell. This shell is composed primarily of сalcium and other minerals the snail has eaten and hardened into a well-formed shell.

The soft-bodied animal is permanently connected to the shell by a strong ligament and other soft tissues. The snail’s shell is used for protection from environmental threats and predators.

2. How long do freshwater snails life?

Nerite snails, Rabbit snails, Mystery snails, Ramshorn snails usually live for 1 – 3 years. Assassin snails can live up to 5 years. Malaysian Trumpet Snails live 1 – 2 years. Pond snail can live up to 3 years. Bladder snails can live for around 1 year. You can read my guides about all of them.

Freshwater snails can vary wildly in their longevity, which is dependent on the type of snail and the habitat in which it occurs. In general, snails that possess an operculum live longer than species without one.

The maximum age of many species living in streams and rivers can exceed five years, whereas most species that prefer ponds and lakes live less than one and a half years. As a general rule, the more nutrients available to the snail, the faster it grows, and the shorter its lifespan. Snails living in nutrient-poor habitats on average tend to live longer.

Related article:

3. Can freshwater snails live in a 1-gallon tank?

Yes, some snails (for example, pond snail and bladder snail) can live in a 1-gallon tank although I would not recommend keeping anything in a gallon tank.

The smaller the tank, the harder the water parameters are to control and the more likely your first time will end in disaster.
Keep in mind that snails eat a lot and produce a lot of bio-load. Without proper control, there will be constantly ammonia spikes.

Relate article:

4. What freshwater snails can I keep in 5 or 10-gallon tank?

Most freshwater snails (for example, Mystery snail, Malaysian Trumpet snail, Ramshorn snail, Assassin snail) will thrive in 5 – 10 gallons tank.

However, 5 gallons might be not enough for Nerite snails. The point is that they prefer algae to any other food and it can be a problem to maintain algae at a certain level in a smaller tank. Otherwise, they will eat all the algae and then starve. Regarding Rabbit Snails, they are way too big and require 20 gallons at least.

You can find detailed guides about all these snails on my blog.

5. Will Nerite snails eat plants?

No, Nerite snails do not eat plants even if they are hungry. They are plants safe. This is one of the reasons, why people love them and keep in planted tanks.
Note: sometimes people confuse grazing on with eating the plant. They only seem to eat dead, dying, or bruised plants.

6. Will freshwater snails eat live plants in the tank?

There are species, which can be safely kept with plants. However, some types of snails do eat healthy plans. These snails are pests and banned in many countries in the world.
Basically, it depends on the species. For example:

  • Nerite snails, Malaysian Trumpet Snails, Mystery snails (Pomacea Brigesii / Pomacea diffusa) do not eat healthy plants.
  • Apple snail (Pomacea canaliculata) feed voraciously on aquatic vegetation. It is on the list of the world’s worst 100 invasive alien species (and top 40 in Europe.).
  • Colombian Ramshorn snail (Marisa cornuarietis) will eat any type of aquatic plants in your tank. 
  • Ramshorn snail can munch on soft plants when they are hungry.
  • Bladder snail and Pond snails are not harmful and they will not touch your plants. However, there are also types of bladder snail (such as Physa fontinalis) which eat live plants and shred the leaves from time to time.
  • Rabbit snails will not touch the plants as long as there is plenty of food. Some aquarists reported that when they are hungry they show a particular interest in Java ferns (read my guide).

Related article:

7. Do aquarium snails need oxygen?

Yes, they do need oxygen as any other living creature. However, they can breathe in different ways. Basically, it depends on their respiratory system for oxygen exchange. For example, freshwater snails with an operculum are descended from marine ancestors and extract oxygen from the water with a single gill. In contrast, snails that lack an operculum evolved from terrestrial ancestors and breathe with a modified “lung.”

Some snails developed both aerial and aquatic respiration (for example, Mystery snail).
Note: The operculum is a hard “lid” on their tails that is made of protein. The hard operculum covers most soft tissue of the foot exposed to a predator when the snail has retracted into its shell.

8. Do freshwater snails need a filter?

Some freshwater snails are extremely hardy and can live even without a filter. For example, Pond snails, Bladder snails, Ramshorn snails, Malaysian trumpet snails are all almost indestructible.

However, I would not recommend keeping Nerite snails, Mystery snails, etc without a filter if you are a beginner aquarist. The point is that you need to control your water parameters and do water changes all the time so the ammonia will not spike.

9. Can freshwater snails live in brackish water?

It depends on the species. For example, Nerite snails actually live and thrive in brackish water. Some types can even survive in full seawater.
Ramshorn snails can tolerate slightly brackish water conditions only in case you gradually increase salinity.

According to different studies (here and here), Malaysian Trumpet Snail can also tolerate brackish water. Another study on Apple snails showed that approximately half of the snails survived at 10 and 15 ppt.

10. Do snails need heated water?

Aquatic snails cannot regulate their body temperature (cold-blooded animals). Therefore, their body temperature depends on the water temperature. It means that they will eat more, grow faster and have a shorter life span at higher temperatures.

The cooler their water is, the slower is their metabolism. At very lower temperatures, they enter a dormancy state in which they become very inactive.

Snails usually do well at room temperature. So if you do not have huge fluctuations in temperature, they do not need a heater.

11. Do snails have brains?

No, technically snails do not have brains. Instead of a brain, they have a set of ganglia (nerve cell clusters, which can contain 4000 – 100000 individual cells often called neurons) that distribute the control of the various parts of the snail. For example:

  • cerebral ganglia supplying the eyes, tentacles, and head
  • pedal ganglia supplying the foot muscles
  • pleural ganglia supplying the mantle cavity
    As we can see, they have a very simple nervous system, which cannot be defined as a brain.

12. Can I keep freshwater snail with Betta?

Actually, it is very hard to keep snails with Betta because of their aggressive fighting nature. Betta fish are territorial fish and do not tolerate tankmates (including snails and shrimp). However, this always depends on your Betta personality, maybe you will get lucky.

Although Betta cannot break snails’ shell, they usually start picking at or nibbling at their eyes and antenna. They can think that these long tentacles are worms. Therefore, snails with long antennas (for example, Mystery snails) are not the best choice for the Betta.

At the same time, Nerite snails have very short eyestalks and antennas and have better chances of surviving in the Betta’s fish tank.
To minimize the chance of your Betta trying to eat your snails:

  • Keep them in a large tank.
  • Make sure your Betta gets a balanced diet.
  • Put the Betta in only after the snail, so the Betta will not be so territorial.
  • Do not provoke the Betta and chose snails with short eyestalks and antennas.

13. Can I keep freshwater snail with Cichlids?

It depends on the fish size and species but in general, I would say that keeping snails with Cichlids is not a good idea. They will pick at them until they die.

Even if they cannot swallow the snail they will go for their body whenever it is exposed. As a result, constant injuries and harassment usually causes the snails to die

14. Can I keep freshwater snail with Puffer fish?

Absolutely not! It is not possible to keep them together because their natural diet consists mostly of snails, invertebrates (shrimp, crayfish, crab) and insects.

Even the dwarf puffers will feast on them. Hard shell will not save the snails. Actually, it will help Puffer fish to keep their constantly growing teeth short.

15. Can I keep freshwater snail with Loaches?

There are many types of loaches. Some of them can be more aggressive than others. Nonetheless, loaches will not be a good company for the snails.
Note: Clown loaches are frequently sold to control snail populations.

16. Can I keep freshwater snails with turtles?

It depends on the size of the turtle and the snail. If your snails are too large, they may have a chance to live. Keep in mind that almost all turtles are carnivores or meat-eaters. Therefore, the ideal diet for them is protein.
Note: Common and Alligator snapper turtles should not be kept with anything else, including others of their own species. They are too aggressive.

17. The best tank mates for freshwater snails?

Almost any type of dwarf shrimp. Dwarf shrimp are peace-loving and non-aggressive creatures (Except Macrobrachium shrimp, which is predatory. They can hunt down or harass to death, snails, and even small fish).

Freshwater snails will benefit your shrimp tank in many ways.You can read more about it in my articles:

18. What do freshwater snails eat?

Almost all freshwater snails are opportunistic scavengers and not picky about what they eat. Naturally, they will eat almost anything, dead fish, dead shrimp or shellfish, organic debris, dead or rotting plant matter, algae, and anything else they find in the tank.

They actively “graze” a variety of surfaces, scraping their food with a specially modified “tongue” called a radula. The radula is covered with tiny, hard, blade-like projections that scrape the surface. These tiny blades tear small bits of algae and organic material from these surfaces.

19. Do I need to feed my aquarium snails?

If you keep the snails in a community tank with fish or shrimp, there is no need to feed them. They will eat leftovers and clean your tank.

However, if we are talking about Nerite snail, in this case, you need to feed them algae wafers because most tanks will not produce enough algae.

20. Best aquarium snail for algae?

If you are looking for the best algae eating snail – Nerite snails are your choice. They are simply amazing! Their main diet consists of algae: Green spot algae, Green dust alga, Brown/Diatomic algae, Hair algae, etc. They will eat it all with pleasure.

Of course, other snails will also consume algae as part of their ordinary diet, but no other snail in the tank will eat as much or as thoroughly as Nerite snails.
Read more about it in my articles:

21. How do freshwater snails reproduce?

Freshwater snails have adapted different reproductive strategies. There are two different modes of reproduction commonly used by freshwater snails.

  •  Asexual reproduction (hermaphroditic).

Each snail contains both male and female reproductive systems, and all individuals can lay eggs. However, individual snails do not self-fertilize, and sperm is exchanged between individuals.
For example, Pond and Ramshorn snails mature rapidly (at 6–8 weeks for Pond Snails, and 4–6 weeks for Ramshorns) and multiply readily (laying up to 100 eggs at a time for Pond snails, and around a dozen at a time for Ramshorns). They are hermaphroditic and both reproduce asexually, and Pond snails can also reproduce sexually (the preferred method). They lay jellylike masses of eggs underwater on plants and on the sides of the container/aquarium. The eggs hatch in about 10–20 days depending on temperature.

Sexual reproduction

There are separate male and female sexes, and males fertilize the female through direct copulation. Females attach their eggs directly to firm, clean substrates such as a rock, log, or aquatic plant. For example, Assassin Snail, Mystery snail, Nerite Snail, Rabbit Snail (you can read my guides about them).

Note: Some freshwater snails reproduce live young and do not lay eggs. In reality, an egg hatches inside the female and the juvenile snail grazes in a special pouch inside the mother’s body.

22. Can freshwater snails reproduce on their own?

Yes, as I have just said, some freshwater species can lay and fertilize their own eggs. Therefore, strictly speaking, they can reproduce on their own (without a second snail).

23. What aquarium snail does not reproduce in freshwater?

Out of all the most popular freshwater snails, only Nerite snail does not reproduce in freshwater. Nerite snail eggs do not hatch in freshwater. They require saltwater to hatch. Therefore, they will never overpopulate your freshwater tank.
Note: Unfortunately they will still lay eggs, which will never hatch.

24. How can I stop Nerite Snails from laying Eggs?

Lots of aquarists complain that their Nerite snails lay eggs everywhere. It spoils the view and in addition, they are very hard to remove. In my guide about Nerite snail I mentioned about three ways of dealing with this problem:

  • Do not keep more the one Nerite snail in your tanks.
  • Keep different types of Nerite snails if you want to have several snails in one tank. As far as we know, they do not crossbreed (there are no studies about it).
  • If you have 2 or more tanks, you can separate all males and females to different tanks. The problem is that it is almost impossible to figure out the sex … Therefore, you will have to wait while they are mating. Note: According to one of the studies, the female snails can store the male sperm capsules for continuous spawning.

25. What is the largest aquarium snail?

Freshwater snails come in a variety of shapes and sizes. However, Mystery snail (Apple snail) is the largest one. The shell differs in size from 40 – 50 mm (1.5 – 2 inches) wide and 45 – 65 mm in length (1.7 – 2.5 inches) in diameter.

26. Are freshwater snails good or bad for a tank?

There are two completely opposite points of view in the relation of snails. I stick to the point that snails are extremely beneficial. Especially if you are a shrimp keeper. They will help you with overfeeding by eating leftovers. Snails will maintain the nitrogen cycle going and prevent gas pockets in the substrate, etc.

Nonetheless, there are still some people who consider them as pests in the aquarium. Frankly saying, if they have too many snails – this is their fault in the first place.
You can read more about it in my articles:

27. Why do my snails have whitish patches on the shell?

If your snails start losing the color in their shell I would strongly advise checking your water parameters ASAP. For example, low pH (less than 7) can cause the shell to erode.

Another potential problem is the low level of calcium. Snail shells are comprised of 95–99.9% calcium carbonate. In addition, a high level of CO2 can also cause their shells to erode and turn white.
Read more about it in my article: “Water Parameters: Everything about pH in Shrimp Tank”.

28. Do snails need a calcium supplement?

Yes, they do need calcium. Calcium is the most crucial element for the snails. Therefore, adding calcium supplements can help ensure their shells are strong and healthy. Additional calcium sources are cuttlebone, crushed egg shells, crushed coral, and liquid or powdered calcium supplements, blanched kale, blanched zucchini, etc.
Read more about it in my article: “How to Blanch Сucumbers and Zucchini for Shrimp, Snails and Fish the Right Way”.

I highly recommend to read my article “How to Supplement Shrimp and Snails with Calcium”.

29. How to tell if the snail is dead or alive?

The only certain way is to smell it. I am serious. When a snail dies, it decomposes very quickly and when it decomposes, it releases a ton of ammonia. It has a strong pungent, disgusting smell. Do not worry, you will not confuse it with anything else. If it does not smell, well your snail is OK.

You can read more about it in my article “Is My Snail Alive or Dead?”.

30. Why my snail is not moving?

If a snail does not move for hours or even days, it does not mean that it is dead. Some snails can hibernate or hide for days (reacting to the stress or digesting food).
So, do not panic, leave it alone for a time being but keep an eye on it.

Related article:

12 thoughts on “30 Frequently Asked Questions about Snails in Freshwater Tanks

  1. Hello. I have a 5 gallon tank with a Beta. In the tank I have two snails, a tiger and a zebra snail. They have been in the same tank for over a year. Up until recently the snails have done a really good job keeping the tank clean and sparkling. However, recently they have stopped doing a good job and the tank is getting really dirty. The snails are still moving, but are no longer doing their job. Do you have any suggestions?

    1. Hi Sandra,

      There can be several reasons. For example, they can be stressed or (most likely) they are simply getting old. As a result, their metabolism slows down and they do not need to eat as much as before.

      Best regards,

  2. Hi, can I put Ramshorn snails in a pond that is fitted with a liner? (Not Rubber) it’s more like a weaved material with a water proof coating, I wasn’t sure if the snails could eat their way through the water proof coating or not. and are they okay with gold fish? Thanks Alan

    1. Hi Alan McRobert,
      Goldfish are omnivores. So, even though snails are not their main food, they can still suck them from their shells.
      Therefore, the real question is how high is the risk?
      I would say that the risk is acceptable, especially if we are talking about the pond, where Ramshorn snails will have more options to hide and breed.
      Could you be more specific, what is this material?
      Best regards,

  3. Hi Michael, can several different types of aquarium snails be kept togather?

    1. Hi Susan,
      Of course, you can keep different types of freshwater snails in the tank unless this is an Assassin snail.
      Best regards,

  4. Michael,
    Hi – I have a question I would be grateful for your opinion on,

    My snails seem to reproduce at an incredible rate, as evidenced by the trail of small snails that appear on the side of the aquarium, almost on a weekly basis, but these smaller snails die off quickly. The aquarium gravel is littered with the shells of small snails. I continue to check the water, but it is always within the ranges required.

    Can you advise what is going on? Are the fish (mostly tetras) picking them off?

    Thanks for your help.

    1. Hi Tim Davies,
      If your water parameters are OK, it looks like that some of your fish have learned to suck them out.
      What snail species are they?
      Best regards,

  5. We have 2 rabbit snails and have noticed one of the snails has been hanging out on top of our other rabbit snail, I know they aren’t aggressive so didn’t think much of it. Today I noticed, I don’t even know what to call them but like small tendrils along the sidewalk of his/her shell. We did the smell test just in case and no odor whatsoever. any idea what this could be?

    1. Hi Deanna Miller,
      Do you have photos of your rabbit snail?
      So far, I have two ideas: they were mating and leeches.
      Unfortunately, Tylomelania sp. often carries leeches.
      Best regards,

  6. Hi, i have a trug in my greenhouse, it’s near the open door, it’s got a lot of ramshorn snails happily grazing away in it,
    my ? is, what is the lowest temperature they can survive in.
    All the best, Gill

    1. Hi Gill,
      I’ve already addressed a similar question in the article about ramshorn snails.
      Planorbella duryi can’t survive outside tropical and subtropical climatic zones. Whereas Planorbarius corneus is more tolerant and can be kept down to 10°C (50°F).
      Best regards,

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