Bladder snails are interesting tank dwellers that have a mixed reputation (depending on who you ask). Some see them as pests that need to be eliminated, and others see them as helpful aquarium cleaners.
No matter what category you fall into, understanding the basic needs of this species will enable you to take the necessary course of action to achieve your desired outcome. This guide will teach you everything you need to know.
Bladder snails (Physa acuta) are an abundant mollusk species that often show up in freshwater tanks unannounced. They are considered an invasive species and are generally considered pests by the fish farming community. These creatures can hitchhike on plants and scatter eggs prolifically, resulting in rapid population spikes that can quickly outgrow a tank!
Despite the bad reputation, bladder snails can be a welcome addition to your fish tank in controlled quantities (if desired). They can function as an effective part of the aquarium cleaning crew and will spend most of their time grazing debris and different types of algae (more on this later).
Whether you introduced them to your tank intentionally or not, learning about this snail (and what it needs) can help you get the most out of the benefits they provide.
These snails may be widespread, but that doesn’t make them any less visually appealing.
Bladder snails have thin, translucent shells. They are slightly yellow in color and may have some distinctive gold markings. You can see the meat of the snail through the snail. It is usually gray with hints of black or purple.
The mantle, which forms the outer wall of the snail’s body, is a bit more colorful. It has bright orange-yellow spots.
As a whole, the shell has a rather interesting shape. It is shaped more like an egg and has a defined tip. Four to five spirals create the characteristic spiral, which moves to the left.
Peeking out from under the shell are thread-like tentacles. The sensory tentacles support the eyes, which are small black dots.
The difference between bladder snails and pond snails
Many people confuse the bladder snail with pond snails of the garden variety. It is easy to confuse the two as they can easily cohabit in the same environment. Bladder snails appear on every continent in the world except Antarctica. In fact, these snails have become so widespread that zoologists don’t know where they originated from!
While they look similar, a closer inspection shows some glaring differences.
The first difference is the size. Pond snails two to six times larger than the bladder snail.
Also, the shell is different. In pond snails, the shell is dull and brown. For bladder snails, it is translucent and yellowish. Even the shape is unique.
Author’s note: Bladder snails are sinistral. This means that the shell spirals to the left, which is quite rare in the mollusk world. Most species, including the pond snail, are dextral and have armor that twists to the right. Also, bladder snails do not have the operculum lid that most snails use to protect themselves.
The last noticeable difference is the tentacles. Pond snails have thick triangular tentacles rather than the thin thread-like ones of the bladder snail.
Under the right living conditions, the average life expectancy of bladder snails does not usually exceed two years. Of course, they can succumb to the disease much sooner. There are no guarantees when it comes to life expectancy.
Author’s Note: That said, the state of its environment does have a significant impact on a snail’s longevity. Generally, dirtier aquariums offer more feeding opportunities for bladder snails. As a result, they tend to live longer and reproduce more often (more on this later).
The average size of a bladder snail is half an inch. If they are lucky, some specimens can reach lengths of 0.6 inches.
These are small mollusks that do not take up much space. However, don’t make the mistake of thinking they won’t affect bioload. Larger populations can have the same impact as larger fish!
Bladder Snail Care
Bladder snails are tough little critters! They don’t need much to flourish in your aquarium. For most aquarists, the goal is to eradicate these invertebrates rather than support them.
We chose to write this from a bladder snail care perspective, but this information will also work for aquarists who want to get rid of the.
Whatever your goals, understanding the basic needs of the bladder snail will allow you to achieve the desired result.
When it comes to tank size, bladder snails have no preferences. They can survive in small gallon tanks and huge ponds! Thanks to their small size, they are quite adaptable independently.
Keep in mind that every living thing you add to an aquarium will have a bioload that will affect the water conditions. Bladder snails are no different.
If you want to keep these snails for cleaning and maintenance purposes, it is best to keep them in a larger tank to lessen the influence they have.
There are no strict rules for the bladder snail. This species is super adaptable and can live in a wide range of conditions. In the wild, they can even live in sewage plants!
Generally, these snails prefer to live in warm water with little or no flow. But for the most part, they are undemanding. As a result, you can focus on the other creatures in your aquarium instead of the snails. Just adhere to the following parameters to ensure the survival of the snails.
- Water temperature: 64°F to 84°F
- pH levels: 7.0 to 8.0
- Water hardness: 12 to 18 dGH (harder water)
When hatched, bladder snails have very soft shells. Almost immediately, they will search for some calcium to harden their armor.
Author’s Note: A decent amount of calcium in the water is essential for the survival of snails. Without it, this species tends to suffer from stunted growth and limited reproductive rates. You can use that fact to your advantage if you’re trying to manage a population out of control.
But if you want the snails to live healthy, consider adding some crushed eggshells or cuttlefish bones.
What to put in your tank
Again, bladder snails are not picky eaters (you’re probably noticing a pattern here).
This species is a bit unique compared to most other snails in the trade. On the one hand, they are lung snails that breathe air.
They have a unique respiratory system that allows them to float, rock, and swim in the water as they see fit. They can remove air from their respiratory system to sink to the bottom or use it to shake off unwanted parasites and insects.
You won’t see them digging in the sand like other snails. They can hide inside the decoration and be covered with a soft substrate, but they do not infiltrate the bottom of the tank. For this reason, they don’t even have a preference between sand or gravel!
The same goes for plants. They prefer to have plants to climb and hide. They also enjoy feeding on decaying plant matter. However, they do not touch healthy plants or feed on thriving vegetation.
Author’s Note: If you want the population to increase, give the snails plenty of natural food sources. That means plants that will decompose over time, driftwood to collect algae, and more. Other than that though, the decor is up to you!
Possible common diseases
Disease is not something many aquarists worry about when it comes to bladder snails.
Technically speaking, they can succumb to the same diseases as any other freshwater mollusk. The most common ailments your snails may encounter are fungal and bacterial infections. Severe cases can cause significant damage to the shell.
Even parasites are possible. However, those tend to be rare with bladder snails. As mentioned above, they can shake the worms and microorganisms off their bodies if they feel an infestation.
Like any other fish or invert, the key to avoiding disease is maintaining tank conditions. Check the water parameters regularly and make any necessary changes to avoid noticeable fluctuations. Also, do quarterly water changes every two weeks to keep ammonia and nitrate levels low.
Food and Diet
Bladder snails have an appetite that won’t stop! They are constantly eating! Not only that, but they will consume pretty much anything you put in their mouths.
Omnivores through and through, bladder snails eat everything from algae to decaying meat to insects. In an aquarium, they tend to function as algae eaters for most of their diet. However, they will also consume food scraps, decaying waste, and much more.
There are many excellent food sources in an aquarium. It’s the perfect environment for these snails when it comes to food!
Author’s Note: However, keep in mind that too much food availability can lead to some problems. Increased snail populations are a telltale sign that you are overdoing your fish food! Try to limit debris and decaying items to ensure the number of snails in your freshwater aquarium is manageable.
behavior and temperament
Bladder snails are a type of tank dweller that “goes unnoticed”. Many don’t even realize they have snails until many months after they’ve been introduced to the tank. Thanks to their small size, they can easily stay out of sight.
Throughout the day, gathering and foraging for food is their main focus!
These snails are in perpetual search for food. Once they find it, they tend to stay in the same area until they wear it out.
Author’s Note: You may see snails “swimming” in the water from time to time. That’s completely normal and it’s usually the snail using its air bladder to get out of trouble.
When they’re not trying to get away from potential predators, bladder snails spend their days crawling on plants, glass tank walls, and more. They do not dig like other species of snails. Interestingly, they can also move quite quickly!
Talking about tank mates for bladder snails is different from talking about mates for other inverts and fish.
Bladder snails can co-exist with almost any freshwater creature. However, the best course of action is to house them with natural predators. Doing so controls the snail population and ensures that you never have to deal with an out of control infestation.
So while this may not seem like a traditional «tank mate» scenario, it is the common course of action for most aquarists. Bladder snails act as feeders of:
- killer snails
- River crab
- yoyo loaches
- betta fish
- green spotted puffer
You will have no problem getting bladder snails to reproduce. They do it naturally without any intervention. These snails reproduce very quickly and can easily overwhelm a tank.
Bladder snails are hermaphrodites, which means they have both male and female reproductive organs. As a result, these snails can reproduce in two ways.
If they don’t have a mate available, they can propagate and self-fertilize internally. This usually occurs when the survival of the snail is at risk. However, it is not ideal as the hatchlings are not as strong as traditional spawning methods.
When two or more snails are together, they can reproduce as expected.
The snails will lay small egg capsules that contain between 10 and 40 eggs. They usually apply them under the leaves of plants and on inconspicuous surfaces. It only takes about a week for the eggs to hatch.
Bladder snails reach maturity in as little as a month, so it doesn’t take long for the population to grow.
Whether you are interested in the care or removal of bladder snails, having a solid understanding of this species is an absolute must if you are a hobbyist.
We hope you have found this guide helpful and feel prepared to handle these creatures in your freshwater tank. If you have any questions, feel free to submit.