Spixi Snail (Asolene spixii)

Choose a freshwater apple snail with a clear identity

The Spixi Snail is Asolene spixii, a freshwater aquatic gastropod in the apple-snail family Ampullariidae. The World Register of Marine Species accepts that scientific name and places the animal in the order Architaenioglossa. The double i at the end of spixii is part of the accepted spelling.

An encyclopaedic summary of Asolene spixii also describes it as a freshwater snail and aquatic gastropod mollusc. It suits a mature, filtered aquarium whose keeper can test the water, provide supplementary food and screen every proposed companion for predation risk.

Decide whether this animal fits your routine

Choose it for a mature freshwater aquarium with an established filter, measurable water quality and a deliberate feeding routine. It grazes algae as part of the general feeding behaviour described for freshwater snails, but its diet still needs supplementation. It is therefore a living aquarium inhabitant rather than a substitute for filtration, water changes or controlled feeding.

Compatibility also requires a positive check before purchase. Pufferfish, loaches and other fish able to eat snails are unsuitable companions. For every other proposed combination, compare water requirements, predation risk and the aquarium’s total capacity rather than relying on a general community label.

You can also browse the current freshwater snail collection when comparing identities and aquarium roles, then return to the exact animal page before deciding.

Select the dispatch size and plan beyond it

One purchase supplies one animal of the selected option. Choose the 1–1.5 cm size or the 2–2.5 cm size through the live selector, and increase the purchase quantity only when you intend to receive more animals. The selector is the place to check the sizes that can be chosen for an order.

The size you select is the size supplied, not the adult size. These measurements describe the dispatch band. They do not establish age, life stage, sex or a final shell size, so make the aquarium decision from the longer-term planning figures rather than treating the larger choice as a confirmed adult.

Sex is guaranteed only when the selected option explicitly states male or female. This Spixi Snail listing has no sex-guaranteed option.

The gallery scene shown here depicts two snails with rounded yellow-and-cream shells, dark spiral bands, pale translucent bodies and long tentacles moving over dried leaves. The gallery images are representative of this type of animal rather than photographs of the exact animal supplied, so colours can look slightly different from the live animal.

Use the planning figures correctly

OATA’s freshwater shrimp and snail guidance gives 17–27°C, pH 6.5–8.0 and 4–18°dH as broad guidance for freshwater shrimp and snails, not an exact optimum for this species. It also gives 3–15°dKH, zero ammonia, zero nitrite and nitrate up to 20 mg per litre above the normal tap-water level. Keep these values together with regular testing rather than choosing one number and ignoring the rest of the aquarium.

For space planning, OATA recommends approximately 20 litres for larger species such as apple snails and says the aquarium needs to be larger when fish share it. It also says popular aquarium snails are unlikely to grow any larger than 5 cm. Treat that 5 cm figure as a planning reference for popular aquarium snails rather than a promise that every Spixi Snail reaches or stops at an exact length.

Prepare and mature the aquarium before the snail arrives

Set up the aquarium around stable biological filtration rather than the delivery date. Freshwater snails add waste and feeding increases the load on the filter, so the beneficial bacterial population needs time to establish before livestock enters the system. Clear water alone is not the test: ammonia and nitrite must both measure zero.

Our guide to preparing and maturing a first invertebrate aquarium gives a useful setup sequence. Apply the same core decisions here: establish the filter, test the water, add livestock gradually and leave enough biological capacity for the feeding that follows.

Build the physical environment

Use aquarium gravel or sand on the base. OATA recommends live plants where practical because they provide cover, while plastic plants and suitable ornaments can provide shelter when live plants are not used. Choose aquarium-safe furnishings and arrange them so the snail can move between sheltered and open surfaces.

• Filter: run an established filter continuously and check that water still moves through it properly.
• Substrate: use aquarium gravel or sand rather than leaving the setup without the recommended base material.
• Cover: provide shelter with live plants or suitable artificial plants and ornaments.
• Water: confirm zero ammonia and zero nitrite before introduction.
• Space: begin with the approximately 20-litre apple-snail planning point and increase it for a community aquarium.

Add livestock at a pace the filter can support

Increase the number of snails or other inhabitants slowly. Every addition increases waste, and extra feeding raises the amount of organic material the filter must process. Adding several animals to a newly matured aquarium at once can leave too few nitrifying bacteria for the new load and lead to new tank syndrome.

For example, an aquarium that has only just reached zero ammonia and nitrite should not receive a large group simply because every animal is small at dispatch. Add conservatively, continue testing and let the filter respond before considering another increase. The same rule applies when fish already occupy the aquarium: their space, waste and feeding must be included in the decision.

Keep every water value within the working range

Maintain 17–27°C, pH 6.5–8.0, general hardness of 4–18°dH and carbonate hardness of 3–15°dKH. Ammonia and nitrite must remain at zero milligrams per litre. Nitrate should not exceed 20 mg per litre above the normal level in the tap water used for the aquarium.

Read our water chemistry guide to understand what each test measures, then use the water parameter matcher to compare measured aquarium values with this range. Test the aquarium itself because local tap-water values and the biological load inside the tank determine the starting point.

Use the readings to make decisions

Do not introduce the snail while ammonia or nitrite is detectable. Those results show that the aquarium is not safely processing its biological load. Check the filter for blockages, review how quickly livestock and feeding have increased, and carry out the conditioned maintenance needed to bring the aquarium back within the working limits.

Track nitrate against freshly tested tap water rather than treating the aquarium number in isolation. If the tap water begins at 15 mg per litre, the group limit means keeping the aquarium at no more than 35 mg per litre. If the tap-water result is 5 mg per litre, the corresponding ceiling is 25 mg per litre. Use the tap-water result to calculate the aquarium ceiling each time you test.

A larger aquarium usually provides more stable environmental conditions, but volume does not replace testing. Keep a written weekly record so a rising nitrate trend or movement in pH and hardness is visible before it becomes a persistent problem.

Feed a measured supplement instead of relying on algae alone

Freshwater snails generally graze algae in the aquarium, but OATA advises supplementing that grazing with algae wafers. Commercial pellets made for freshwater shrimp can also be used for both shrimp and snails. This routine gives the animal a planned food source even when visible algal growth is sparse or changes over time.

Feed two or three times a week. Allow at least 30 minutes for the snail to reach and eat the wafer or pellets. That access period matters for a slow-moving animal, but it is not a reason to leave persistent excess in the aquarium indefinitely.

Judge the portion by access and leftovers

Place the food where you can confirm that the snail reaches it. After the feeding period, inspect the aquarium for material that remains uneaten. Reduce the next portion when food repeatedly persists, because decomposing leftovers release waste into the water and can push the aquarium away from zero ammonia and nitrite.

Keep the feeding claim realistic

Grazing can contribute to algae control, but it does not remove the need to manage light, feeding, filtration and water changes. Do not increase the number of snails solely to address visible algae without first checking whether the aquarium can process the additional waste and supplementary food.

Avoid turning the feeding routine into an unmeasured daily top-up. Feed two or three times each week and allow enough observation time to confirm access. Consistent measured feeding is easier to adjust than adding more food whenever the aquarium looks clean.

Protect the biological filter during weekly maintenance

The RSPCA’s aquarium filtration guidance explains that biological filters support bacteria which convert toxic ammonia to nitrite and then to the safer nitrate. OATA also describes a filter as essential for freshwater shrimp and snail aquariums. Keep it running and maintain it in a way that protects that bacterial population.

Complete the weekly water routine

Carry out a 25% partial water change at least once every week. Use a siphon to remove concentrated solid waste from the gravel where needed. Treat replacement tap water with a conditioner that removes chlorine or chloramine before it enters the aquarium.

Test the water at least weekly for ammonia and nitrite, and include the other working values in the routine so trends remain visible. A clear aquarium can still have harmful dissolved waste, so visual appearance never replaces a test result.

Clean the filter without stripping its biology

Check the filter for blockages. When reusable media needs cleaning, rinse it lightly in aquarium water removed during the partial water change. Do not run it under the tap because any chlorine or chloramine present may kill the beneficial bacterial population established in the media.

If ammonia or nitrite appears after livestock or feeding increases, treat that result as a warning that the biological load has overtaken the filter’s present capacity. Pause further additions, restore the maintenance routine and keep testing until both readings return to zero.

Follow the store acclimatisation steps on arrival

Prepare for the parcel before its delivery window and make sure someone can receive it. Test the aquarium in advance, confirm that ammonia and nitrite are zero, and have the final placement ready. The full delivery and Live Arrival Guarantee policy contains the current delivery conditions and the actions required for a claim.

Film, float and release in the correct order

1. Have someone present to receive the parcel so it is not left unattended.
2. Before opening it, start filming the sealed parcel with the outer box visible.
3. Open the parcel in one continuous take and show the animal still inside the sealed bag before anything is disturbed.
4. Float the bag for 20–30 minutes.
5. Release the animal without pouring the bag water into the aquarium.

Keep the recording and your order number if you need to contact us about a Live Arrival Guarantee claim.

Keep the first week controlled

Continue the established feeding schedule rather than adding repeated extra meals to encourage movement. Observe activity, appearance, colour and interest in food, then record any change from the animal’s developing normal pattern. Check for uneaten food after each planned feed.

Test ammonia and nitrite during the normal weekly routine and sooner when behaviour changes across several inhabitants. A new snail and its food add biological load, so the first result after introduction is useful when deciding whether the filter can support any further additions.

Avoid adding more livestock during the same settling period merely to create a group. Snails are not social creatures under the group guidance, and gradual additions give the filter bacteria time to increase as the waste load rises.

Respond to health changes by checking the environment first

Learn the animal’s normal pattern through regular observation. OATA recommends watching freshwater snails for changes in activity, colour, appearance and feeding. Increased inactivity, restlessness, unusual behaviour, a darker or paler appearance, visible discolouration, lesions, abnormal growths or reduced interest in food all deserve attention.

Start with measurable checks

When a change appears, test temperature, pH, ammonia, nitrite and nitrate, then compare general and carbonate hardness with the working range. Inspect filter flow and look for a recent increase in livestock, feeding or persistent leftovers. These checks identify environmental problems that can affect more than one aquarium inhabitant.

Keep copper away from the snail

Freshwater shrimp and snails are very sensitive to copper and will die if exposed even to low levels. Check every aquarium treatment before use and choose only products labelled as safe for the invertebrates in the system. Include shared nets, containers and other equipment in that check when they have been used in a treated aquarium.

Do not select a disease treatment from one sign alone. A behaviour or colour change can coincide with unsuitable water, a disrupted filter or contaminant exposure, so complete the environmental checks before introducing another chemical to the aquarium.

Scale space and filtration as the aquarium population grows

Use approximately 20 litres as the starting planning point for an apple snail, then increase aquarium size when fish share the system. The larger aquarium is more likely to maintain stable temperature and water quality, but only when its filter and maintenance routine match the total population.

Do not convert the planning point into a simple litres-per-snail formula. Fish, shrimp, other snails, feeding and filter capacity all affect the biological load. An aquarium that already carries fish cannot allocate the same water volume again to a new animal without considering the existing waste and food input.

Keep one or add several for practical reasons

Snails are not social creatures in OATA’s guidance, so there is no need to buy several to create social company. One purchase quantity supplies one animal, and one can be planned for without building an artificial group requirement.

If you choose several, increase their number slowly. Confirm zero ammonia and nitrite after each stocking change, allow the filter bacteria to respond and check that each animal reaches the supplementary food. More animals mean more waste and a greater chance of uneaten food accumulating.

Plan around OATA’s reference that popular aquarium snails are unlikely to exceed 5 cm, while recognising that it is not an exact final-size promise for this animal. That approach leaves room for growth without treating the 1–1.5 cm or 2–2.5 cm dispatch label as a permanent measurement.

Screen every fish for predation before mixing it with the snail

Freshwater snails can share an aquarium with many other inhabitants, but mixing them always requires caution because common aquarium fish may eat them. The decisive question is not whether a fish is commonly called peaceful; it is whether that exact species can consume or injure a snail.

Avoid named snail predators

Avoid pufferfish and loaches because OATA identifies them as fish that can eat snails. Do not use the shell as a reason to test this combination. The risk comes from the fish’s feeding behaviour, and an established aquarium does not remove it.

Apply the same rule to every proposed companion

• Predation: exclude any fish able to eat the snail.
• Water: confirm that the companion can remain within 17–27°C, pH 6.5–8.0 and 4–18°dH without compromising its own needs.
• Space: increase the aquarium beyond the apple-snail starting point when fish share it.
• Filtration: include every inhabitant and its food when judging biological capacity.
• Treatments: make sure the whole aquarium can be managed without exposing the snail to copper or another product unsafe for invertebrates.

For combinations outside the named pufferfish and loach risk, compatibility depends on the exact fish, its feeding behaviour, shared water requirements and the aquarium’s capacity. Do not turn the absence of a named warning into a universal guarantee.

Assess the whole community rather than one tank mate at a time

A proposed companion can pass the immediate predation check and still make the aquarium unsuitable when the total population is considered. Add the adult planning needs, waste, feeding and water requirements of every inhabitant before deciding whether there is enough capacity.

Check the shared routine

The aquarium must keep ammonia and nitrite at zero after the planned community and its feeding are in place. Nitrate must remain no more than 20 mg per litre above the normal tap-water level, and the filter must continue to run without blockage. If maintaining those limits already requires urgent correction, do not add another animal.

Every inhabitant must also tolerate the same temperature, pH and hardness. A value inside the snail range is not automatically right for a proposed fish, so check the exact companion’s own requirements and use only the overlap.

Include treatment restrictions

The presence of a snail changes which aquarium treatments can be used safely. Copper sensitivity means a community plan must account for the invertebrate before any whole-tank product is added. A fish combination that routinely depends on a treatment unsafe for snails is not a workable shared-care plan.

When the feeding behaviour of a proposed fish remains unclear, contact us with its exact name, aquarium volume and current water values. That information allows a stocking assessment based on the real combination rather than a broad community label.

Answer the main questions before choosing

How big does a Spixi Snail get?

Plan beyond the dispatch measurement. OATA says popular aquarium snails are unlikely to grow larger than 5 cm. Use this as a planning reference for popular aquarium snails, not an exact Spixi Snail maximum.

What size aquarium does this animal need?

OATA recommends approximately 20 litres for larger species such as apple snails and says the aquarium needs to be larger when fish share it. Use a mature, filtered setup with zero ammonia and nitrite.

How many Spixi Snails should I keep together?

OATA describes snails as non-social, so one can be kept singly. Add any further animals slowly while checking space, food and the filter’s ability to keep ammonia and nitrite at zero.

Does this snail suit a beginner?

It suits a keeper who can prepare a mature filtered aquarium, test the water, complete weekly maintenance and manage feeding. Do not place it in an uncycled first-day setup.

What does a Spixi Snail eat?

OATA advises letting freshwater snails graze algae and supplementing them with algae wafers or commercial shrimp pellets two or three times a week. Allow at least 30 minutes for feeding and remove persistent excess.

What temperature and pH does Asolene spixii need?

Keep it at 17–27°C and pH 6.5–8.0, with general hardness of 4–18°dH. These are OATA’s freshwater shrimp and snail values and are not a species-specific optimum.

Is the Spixi Snail aggressive or likely to nip fins?

Plan compatibility around risk to the snail: OATA says snails should not be mixed with fish that can eat them. Avoid pufferfish, loaches and any other fish able to eat snails.

Which kinds of animals can live with this snail?

Choose aquarium inhabitants that cannot eat it and whose temperature, pH and hardness requirements overlap. OATA specifically says to avoid mixing snails with fish that can eat them, such as pufferfish or loaches.

How does a Spixi Snail arrive alive in the UK?

Film every delivery continuously from the sealed parcel as it is opened, with the animal still in the sealed bag before anything is disturbed. Have someone present to receive the parcel, float the bag for 20–30 minutes, then release the animal without pouring the bag water into the aquarium.

Consult the reference bibliography

• World Register of Marine Species: accepted scientific name, family and order.
• Wikipedia, Asolene spixii: concise freshwater natural-history context.
• Ornamental Aquatic Trade Association: freshwater shrimp and snail guidance covering water, aquarium preparation, feeding, maintenance, health and compatibility.
• RSPCA aquarium environment guidance: biological filtration and the conversion of ammonia through nitrite to nitrate.