Perfect for keeping a controlled number – does not reproduce in freshwater
Peaceful, safe with any fish and large enough not to get eaten by goldfish
The #1 reason you will love Nerite snails is because they are algae eating machines. Some people call them “algae balers.” At a ratio of 1 snail per gallon, we found they completely eliminated brown diatom infestation (brown algae) as well as green algae and film algae in just 48 hours! They are thorough little janitors and slowly cruise around the tank, using their adorable “buck teeth” to scrub the glass, plant leaves and substrate. We’ve found in our tests that they beat every other kind of snail on this list for algae eating. Other snails will partially help, whereas these guys totally eliminated it. They save suffocating plant leaves by carefully and delicately removing the algae until they are completely clean and the plant can properly photosynthesize. At the right stocking level, you will not have to ever scrub your glass to get rid of algae again. They do NOT reproduce in fresh water (no risk of overpopulation).
Nerite snails are popular among goldfish enthusiasts. They are among the best of algae eaters and will even go after very stubborn green spot algae. Nerites come in a variety of interesting color patterns, including Tiger Stripe, Tiger Eye, Midnight Black, Zebra, Sun Thorn, Horned, Black Racer, Red Racer, Gold Racer, Lightning Bolt, Hair Thorn, Marble, Plain and more. The horned and thorn varieties have spiky protrusions on their shells. These snails can live up to 2 years, though 1 year is most typical. There is no worry about the population getting out of control, as Nerites can’t reproduce in freshwater. They will sometimes lay eggs, which look like little grains of salt on the inside of the tank, but they will not hatch and can be scrubbed off.
Mystery snails make a fascinating addition to any goldfish tank. They are especially suited to larger sized goldfish. They usually learn to keep their antennaes in around the goldfish while they cruise around the tank. They will eat algae with a vengeance, and you can always see where they’ve done their work by the “tracks” they leave on the glass and ornaments. In addition to algae, they love to munch on veggies like spinach, cucumber and leafy greens. Cucumber skins are a good choice for them, as goldfish won’t usually go for those. Their population can be easily controlled by removing the clutches of eggs they lay on the sides and lid of the tank (above water). Their shells will be the most beautiful and healthy when provided with a calcium supplement in their food. I’ve used calcium-enriched veggie sticks with success, though getting calcium in supplement form to the snails in food form can be tricky if the goldfish get to the sticks first. They come in a wide variety of colors, including brown striped, peppermint (red and white stripe), golden, jade (green), blue, white, dark purple stripe, light purple stripe and more.
Japanese Trapdoors are an unusual and peaceful variety of snails and one of the largest in the hobby. They are a popular choice for both indoor aquariums and ponds useful as scavengers and algae-destroyers – and are one of the few snails that can survive in cold northern climates. With a lifespan of up to 5 years, these snails do not reproduce quickly and have far fewer offspring. They are called “trapdoor” snails because of the hard plate that closes them in when they are withdrawn inside their shells. It is a good idea to ensure the waterline of your aquarium isn’t too high since they occasionally come out of the water to breathe air.
Creates a self-sustaining population depending on available food
Comes in several very pretty colors
Eats algae and detritus to keep your tank healthy
The Ramshorn snail is a fast-growing and beautiful snail that reaches a size of 1-2″ long. It is named for its beautiful whirling shell that is flat and has no spire. Their eyes do not protrude on stalks, but are located underneath their antennae. Popular colors include copper (brown), red/pink, blue and gold. There are also leopard-spotted varieties. A common complaint about these snails is how quickly they can reproduce. However, they can be used as a food source, as goldfish are a natural predator of this snail and will take care of any small ones they can find. They will also naturally die off when food is scarce. In this way their population is kept in check and your fish get extra nutrition. I have never had a problem with these overpopulating in any of my goldfish tanks. Small snails can be grown to adult size in a glass jar or similar with a live plant.
Beautiful sparkly shell in the right light as adults
True pond snail survives cold winters
Eats algae & not your plants
The Great pond snail (Lymnaea Stagnalis) has a beautiful spired shell with sparkling flecks on the body and shell that glimmer in the right light. They reach between 1-2″ long as adults.
A cold-tolerant snail that can adapt to a wide range of temperatures, this is one of the few snails that can survive winter outside. Because they eat algae with a vengeance while leaving healthy plants alone, they make an excellent choice for little tank maintenance helpers and restore the balance of the aquarium.
Fascinatingly enough, it is mentioned in the earliest record of a goldfish aquarium as a natural solution for reversing algae problems:
“The decaying leaves of the vallisneria produced a slime which began to affect the [gold]fish injuriously : this impurity it was necessary to get quit of. Mr Warington introduced five or six pond-snails (Limncea stagnalis), ‘which soon removed the nuisance, and restored the fish to a healthy state, thus perfecting the balance between the animal and vegetable inhabitants, and enabling both to perform their functions with health and energy. So luxuriant was the growth of the vallisneria under these circumstances…” (Source)
While they can lay many eggs, these will quickly be hunted down by goldfish and eaten, preventing overpopulation. They are also a nutritious source of food.
Because they can grow much larger than, say, a bladder/tadpole snail or a mini ramshorn snail, they make fantastic companions for the goldfish. In addition to keeping algae to a minimum, they also break down fish waste into a form that is easier for the filter bacteria to process, stabilizing the tank.
If you purchase young snails, the babies can be grown out in a jar or small tank to adult size before adding them in with your goldfish so they won’t get eaten. At the same time you are quarantining them to prevent the transmission of any pathogen, so it is a double bonus. No filter is necessary; just add a live plant to keep the water clean. You will notice the snails will keep every leaf spotless. The warmer the temperature the faster they will grow. Supplying them with a good food source that includes calcium on a daily basis will give you the best results in terms of size and shell health.
General Snail Care Tips
Beware of Copper
Snails are very sensitive to copper.
As in… it kills them.
Tap water can also contain copper.
I use this water conditioner to be sure to eliminate heavy metals and copper from the water. I had issues with snails dying off from copper but once I switched to this, no more problems with copper toxicity.
Medications that contain copper can kill your snails.
Feed a Calcium-enriched Food
Snails rely very heavily on calcium to develop their shells.
Without calcium in their diet, most species of snails will experience shell problems such as pitting, cracks and irregular growth.
They keep your aquarium clean of algae and also help break down nasties into a form that bacteria can use.
Plus, they are super fun to have 🙂
1. Aren’t snails messy?
Snails only add to the bioload what you give them in addition to their natural food source.
If you are like me, you may have looked at a container of these little guys and noticed all the poop around them and thought to yourself, “look at all that extra waste these creatures are adding to my tank.”
The truth is, they are NOT adding extra waste unless you feed them extra.
They are only breaking down what’s in your aquarium even further, so it is more readily available to bacteria, which actually helps your aquarium’s stability.
Stuff like dying plants, fish waste and uneaten food is kept from rotting and messing up the water quality even more.
If you choose to feed your snails some kind of pellet or wafer, then yes, they are adding to the bioload of the aquarium, but maybe that’s not a bad thing if you want to grow your cleanup crew.
Finally, I would add that it is a good idea to supplement your aquarium with probiotic bacteria on a weekly basis.
These bacteria take waste by-products (especially what the snails create out of your tank’s waste) and consume it.
This does two things:
It keeps the aquarium cleaner.
It out-competes bad bacteria.
The second is actually very important.
Whether you have snails or not, your aquarium is constantly producing waste that throws off the balance of your tank and favors the growth of harmful bacteria in your water that make your fish sick. And without good bacteria to consume the by-products of fish waste and rotting detritus, bad ones will take over.
Snails are a set in the right direction of helping to balance the tank’s ecosystem, but in the end it comes down to bacteria.
2. Don’t snails destroy my plants?
Snails will only destroy your live plants if they are starving.
If they have enough food (like algae, uneaten fish food, etc.) they will only eat unhealthy, dying leaves.
One really nice benefit of keeping them with plants is that they help to clean algae off the leaves of slower-growing plants and remove detritus that gets caught in the leaves or needles of finer plants.
If you want to prevent starving snails from eating your plants, a natural predator is a great option.
The best part?
Goldfish are already a natural predator of snails and will eat most of the ones that can fit in their mouths.
This means they won’t eradicate them if there are still some adults that are too big to eat.
3. Won’t snails reproduce out of control?
If you are worried about this, you can go for a snail that doesn’t reproduce much or at all, such as a Japanese Trapdoor or Nerite.
The population of other kinds of snails is self-regulating.
If there is a lot of food available, then you can end up with a lot, but maybe that’s what your tank needs.
Having a lot of snails is not necessarily a bad thing.
They won’t reproduce much or they will die off if there is not much food.
Here’s a really good video I would encourage you to watch if you are wondering if snails are a good thing or not for your aquarium:
4. Will Goldfish Eat Snails?
Yes and no.
Bigger snails that can’t fit in their mouth will most likely not get eaten.
I say most likely because some large, slim-bodied goldfish have been known to “attack” bigger snails and suck them out of their shells.
But this is not the norm.
Most of the time, as long as the snail is big enough not to fit in the mouth of the fish, you will be fine – especially if your fish are smaller or of the fancy variety.
For this reason, larger snails like Nerite or Mystery snails are a popular choice.
They will eat little baby snails when they can find them.
So if you don’t want this to happen you can either separate the little baby snails into a separate container to grow them out or you can try to provide lots of live plants to shelter them with.
It can also be a good thing to help keep their population under control if you have some natural predation going on.
5. Can Snails Transmit Disease to Goldfish?
Yes, they can.
But this can be prevented through proper quarantine.
Quarantining snails is actually very simple.
Probably easier than quarantining any other tank mate.
You don’t need medications.
You don’t even need a quarantine tank.
I use a glass jar filled with water (dechlorinated with copper removing conditioner) and throw in a stem of a fast growing plant like hornwort.
The plant keeps the water oxygenated and gives the snails something to eat tiny particles off of.
Set it in a windowsill for 28 days and boom, your set.
Why does this work?
Any parasites the snail might be harboring that are harmful to goldfish will die without a host in 28 days.
An avid goldfish breeder and keeper for nearly 20 years, Meredith Clawson is the founder of the Pure Goldfish website and author of the book The Truth About Goldfish. Pure Goldfish has been featured in Wikihow, Wikipedia, The Aquarium Guide and more.