Nerite Snails are one of the best options when trying to keep your tank clean, whether it’s freshwater or saltwater. They spend most of their time moving around the tank, consuming any algae in their path. Snails are ideal for the beginner, as they are likely to make a few mistakes. They are very easy to care for and have few demands once you’ve added them to your tank.
They are also easy to breed so your snail population can quickly multiply. At less than an inch long they won’t worry anyone who’s space-conscious and they can be kept in smaller tanks.
These snails are from the Neritidae family, which contains over 200 species. Most of these species are from brackish, seashore waters, but a few live in rivers and streams. This means that some can be used in freshwater tanks and others in saltwater setups.
Those used in freshwater tanks originated from brackish waters in Eastern Africa, so they would normally live in a mixture of salty seawater and fresh river water. Saltwater species tend to be from the Pacific or Caribbean coast.
Many of these snails have adapted to live in freshwater so make perfect tankmates for your freshwater aquarium; they should live for 1 – 2 years and grow up to an inch.
The main reason that people add these snails to their tank is that they’re one of the best algae eaters around. This helps to keep tanks clean, as long as they aren’t overstocked. Snails aren’t very active, but they’re peaceful creatures and shouldn’t cause any problems for the rest of your fish. They can become easy prey though, so they’re not suitable for a tank full of large, aggressive fish that might want a snack.
You might sometimes notice your snail appears to have fallen over, their muscle foot is very flexible and they can usually flip themselves back over. You might want to give them a helping hand if they can’t!
Snails also need sleep, just like we do, but their sleep happens in 2 – 3 day cycles rather than the 24-hour cycle we follow. So, how long does a snail sleep? They are thought to have around seven bursts of sleep over a 13 – 15 hour period and they then are able to have around 30 hours of activity.
A snail’s anatomy includes a hard, coiled shell on top of a muscular «foot» which moves side to side to push the snail forwards. They also have four sensitive tentacles. Nerite Snails will grow up to 1 inch if kept healthy. Different species have different colours and markings, but they share the same basic shape and structure.
Zebra Nerite Snails have stripes across their shells that point towards the centre of the coil. The stripes are usually black and yellow in colour, but the shade can vary.
Tiger Nerite Snails are similar to the zebras, except they’re a much more intense orange. The stripes are a lot more jagged too which gives each snail a slightly different look.
Olive Nerite Snails are commonly kept in aquariums. Their name gives away their colour, but most of them don’t have a pattern on their shell. The black line of the coil stands out against the olive colour and produces a simple but attractive look.
Horned Nerite Snails are a little different to the last three. They have thick black and yellow stripes, but along one stripe is a series of dark «horns».
They’re mostly found in coastal habitats such as mangroves and estuaries which have plenty of rocks and other surfaces on which algae grow; if these can be replicated in your tank then they’ll thrive.
Saltwater setups will need hiding spots, these can be made using live rock. Live rocks let your snails take advantage of the algae that grow on their surfaces.
A snail has four tentacles which are very sensitive. A fine-grained, sandy substrate reduces the risk of scratching. Calcium substrate is best because it means that the snails always have a good supply of calcium, which is needed for a strong shell.
The water parameters are the same for both saltwater and freshwater snails, they prefer a high pH of 8.1 – 8.4 and a temperature of 72 – 78°F. Saltwater tanks should be kept to the salinity of 1.020 – 1.028sg.
A small amount of true freshwater species live in habitats such as forest and mountain streams. As we mentioned before, some marine and brackish snails have also adapted to live in freshwater. Fresh and saltwater tanks have very similar setups.
Rocks and driftwood are ideal for freshwater tanks. Make sure to provide plenty of caves to act as hiding spots, even though most of their time will be spent out and about.
Similarly to saltwater setups, your freshwater tank should also have a fine-grained sanded substrate.
Breeding Nerite Snails:
One reason why these snails are so popular for freshwater aquariums is that fish stores often tell people they won’t breed in freshwater tanks. This is not necessarily true.
Nerite Snails will breed and lay eggs, but they don’t hatch as the larvae need brackish water to survive. When this happens you can try to remove the snail eggs by scraping them off or, if you want to continue the breeding process, remove them to appropriate water conditions.
You can either let your snails reproduce in freshwater and move the eggs, or just start the process with snails that are already acclimatized to living in saltwater.
Most snails reproduce asexually, but nerite snails are an exception. The female will produce eggs for the male to fertilize, like fish. The eggs will then be spread throughout the tank and develop into larvae if provided with brackish water conditions.
Once hatched, the young are very small, to the point where they might get sucked into the filter inlet. A Sponge Filter would make this virtually impossible.
If breeding snails is your aim, moving them to a brackish water setup will give you the best chance of success (this is their natural habitat). If you are moving the snails from a freshwater setup you should gradually acclimate them first; there are many ways to do this.
One way is to remove the snails with some of their old tank water, then slowly add water from the new environment over the next couple of hours until the water level has tripled.
An ideal breeding tank will contain as many snails as possible with a fairly even ratio of males to females. The size of the group depends on the size of the tank you have, but a small group of five should be fine. They will start to breed once they’re comfortable in the tank.