How Many Snails Per Gallon Freshwater?

Feb 7, 2022

How Many Snails Per Gallon Freshwater?

“You will learn along the way.” This is what most aquarists say as advice if you are a novice in this field. But there are some things you should learn and do right before venturing into this hobby. 

And among those is choosing the right tank size for your little friends. I have seen snail custodians approving small tanks for beginners. But, au contraire, this is a piece of misleading advice. 

So, is there any hard and fast rule to determine how many snails you can keep per gallon?

Let’s find out.

How Many Snails Per Gallon Freshwater?

Although it depends upon the size of the snails, on average, keep no more than 2 snails in a 5-gallon tank. This will ensure enough space and bountiful food for your slushy pals. 

An apple snail (5 inches in diameter) is enormous compared to a horned nerite snail (1 inch in diameter). So, based on the recommendation mentioned above, 2 snails per 5 gallons might seem obscure. 

Do not house more than 5 in a 5-gallon tank for smaller snails. As for bigger ones, you shouldn’t keep more than 2.

And if you feel like I have confused you with my contradictory advice, a simple suggestion would be: Go for a bigger tank! 

Here’s a list showing commonly available aquarium sizes and the number of snails (3 inches or more in diameter) that can go inside it:

Aquarium CapacityNo. of Snails
5-Gallon TankUpto 2
10-Gallon Tank2 to 5
15-Gallon Tank5 to 10
20-Gallon Tank10 to 12
30-Gallon Tank12 to 15
40-Gallon Tank15 to 20

Here’s another chart to help you understand the tank measurements and their respective weights:

Tank SizeMeasurements (length x breath x height)Empty WeightFilled Weight
5 Gallon16” x 8” x 10”3 lbs.27 lbs.
10 Gallon20” x 10” x 12”11 lbs.111 lbs.
15 Gallon24” x 12” x 12”21 lbs.170 lbs.
20 Gallon (Long)30” x 12” x 12”25 lbs.225 lbs.
30 Gallon36” x 18” x 12”48 lbs.348 lbs.
40 Gallon (Long)48” x12” x 16”55 lbs.455 lbs.

The “An Inch Per Gallon” Rule With Snails

This rule is an oversimplified explanation of choosing the right number of fish for a tank – especially those less than 3 inches in length. But it also works for snails.

Most snail species do not grow more than 3 inches. Only a handful of them will reach that hallmark in their lifetime. 

Also, they do not cover a distance as quickly as fishes do – which means there is more space for everybody. This is why “an inch per gallon” is a helpful rule to abide by for first-time snail keepers.

Here is a list of some of the most sought-after snails with their respective average size:

SpeciesLength In Diameter
Zebra Nerite Snails (Neritina natalensis)1.5 inches
Tiger Nerite Snails (Vittina Semiconica)1 to 1.5 inches
Horned Nerite Snails (Clithon corona/diadema)0.6 to 1 inch
Mystery Snails (Pomacea bridgesii)2.5 to 3 inches
Japanese Trapdoor Snails (Cipangopaludina japonica)2 inches
Rabbit Snails (Tylomelania sp.)3 to 5 inches
Black Devil Snails (Faunus ater)2 to 3 inches
Apple Snails (Ampullariidae)5 inches
Ramshorn Snails (Planorbidae)1 to 2 inches
Pond Snails1 to 3 inches

There are a bunch of things that one should weigh in when deciding on a stocking number for a snail tank. Keep reading to know!

Snails Proliferate Rapidly

In my experience, I have found that people have very strong opinions about raising snails. They either love or despise them. Some find snails fascinating, while some think of them as no less than pests. 

Their ability to proliferate in quick successions often puts your tank at the risk of snail infestation. For instance, pond snails and ramshorns are two of the most prolific breeders in the snail community. They can make you rethink your decision to get a small tank. 

So, if you are housing fast-breeding snails, you need to get a larger tank and work strategically to control their population boom.

Do Not Underestimate Snails

Most fish aficionados believe that their tank’s algae supply will meet the invertebrae’ algae demands. But this is so wrong. Algae-eating snails, like the nerite snails, can empty your tank’s algae reserve within days.

So, the algae from your tank alone, especially if it is a small tank, won’t be able to satiate your snails’ dietary needs.

However, remember that not all snails eat every kind of algae. On top of that, there are snail species that do not eat algae at all. 

Therefore, if you want a self-sustaining algae mechanism, you better go big – no less than a 40-gallon tank. Biofilms, algae, and necessary bacteria can only grow in abundance if the breeding ground is big. 

Do Growth Rate Of Snails Depend Upon The Size Of The Tank?

No, there’s no direct relationship between a snail’s size and the size of the tank. Nonetheless, harboring a rout of snails in a fun-size tank will provoke competition for food – resulting in malnourished snails with stunted growth.

You Might Also Like To Read:

What Happens When You Put Salt On A Snail?

How To Acclimate Snails In Freshwater? What Happens If You Don’t Acclimate?

How To Get A Snail Out Of Its Shell?

Minimum Tank Size Requirement For Freshwater Snails

The minimum recommended tank size depends upon the snail’s species. For example, if your snail’s maximum growth potential is no more than 3 inches, you should at least get a 3-gallon tank. 

But, if your snail’s average size is more than 3 inches, a 10-gallon tank will be the minimum requirement.

Should You Keep A Snail-Only Tank?

Keeping a snail-only tank is fine as long as you can commit to providing an ample diet without overcrowding the habitat. The main benefit of having a snail-only tank is that you won’t have to worry about frequent water changes. Also, the threat of predation will be zero – well, of course, unless you keep assassin snails.

However, there are some things that you should be mindful about when it comes to keeping a snail-only tank. They are:

  • Lack of monitoring can result in an infestation. Snails breed like rabbits. Most freshwater snails are hermaphrodites, which means both sexes can produce offspring. 
  • Some find snail-only tanks aesthetically unpleasant.
  • Beware of copper. It is a guaranteed snail killer.

Final Words: How Many Snails Per Gallon Freshwater?

A rule of thumb would be two snails for a 5-gallon tank. But, be that as it may, I have seen people keeping ‘countless’ snails in small tanks. 

Personally, I recommend getting a 20-gallon tank for freshwater snails. This way, you can house not only your snails but also several other tankmates to make your tank visually appealing. 

Relevant Articles:

How Long Do Freshwater Snails Live?

How Do Freshwater Snails Kill Humans?

What Does Snail Taste Like? Better Than Viagra??

rohit gurung author at urbanfishkeeping

About Rohit Gurung

My never-ending love and fascination with Aquascaping started when I received a red-eared turtle for my 10th birthday.

Apart from researching and writing, I spend hours gazing at my 3 turtles. And yeah, I bask alongside them too.