Why is my Snail Turning White? (With 6 Essential Solutions)

Snails are an excellent addition to fish tanks. However, quite frequently, I noticed that they changed color so that their shell was turning white. As time passed, I learned a few reasons for the phenomenon. There were even cases when I improved the situation. Now, I am willing to share my experience.

Snails’ shells typically turn white due to health deterioration, secondary to ongoing stress, abrupt temperature changes, and acidic water. That also happens in tanks that feature low calcium or elevated copper concentrations. In some cases, snails turn white due to the lack of direct sunlight.

As we proceed, I will share a few techniques to help you deal with the whitening snail issue. I will also mention in which cases there is nothing you can do, and when it is not actually the snail’s shell that has turned white.

Why is my Snail Turning White?

White snails are nothing new. However, if your snails started as a different color, and then they turned white, there might be a reason to worry. Or at the very least, you should ask yourself some questions. 

Some factors that can cause snails to turn white include:

1. The Snail’s Health Has Deteriorated

Discoloration in snails can be a sign of deteriorating health. You can blame a snail’s poor health on a variety of factors. That includes poor feeding, a crowded tank, unstable parameters, and dirty water, to mention but a few. 

A healthy snail isn’t that difficult to spot. It is not only active, but it has a healthy appetite, and the color of its shell is stable and even. Once the creature’s health changes for the worst due to stress, bullies, drastic temperature changes, and the like, a loss of color is just one among the many signs you will notice. The others include lethargy, loss of appetite, and a lot of hiding.[1]

2. Insufficient Sunlight Exposure

Several questions are surrounding the impact of sunlight on snails that science hasn’t definitively answered. On the whole, aquatic snails are not fans of the sun. You are discouraged from keeping their tanks in direct sunlight.

If you observe them during the day, you will notice that they always take refuge behind the foliage in their aquarium in the presence of sunlight. That being said, some aquarists have theorized that the absence of sunlight can affect the snail’s health.

That is because the sun enhances the rate at which Vitamin D3 is absorbed.[2] Therefore, the absence of sufficient sunlight could cause discoloration. On the other hand, an abundance of sunlight can have a similar effect. This is also true for UV light.

Plenty of aquarists use UV light to illuminate their aquariums, and faded shells result from this practice. It would help if you experimented with your snails to determine whether or not this is true. 

As was mentioned, the effects of sunlight on the snail’s color have been primarily noted by aquarists. The theory isn’t backed by scientific research. You have to wait and see whether your snails will respond positively to a change in the illumination.

3. Low Calcium Concentrations

If your snails are losing the color in their shells, calcium is the most likely culprit. Snails depend heavily on calcium. They use it to not only grow their shells but also to maintain and repair them.[3]

A calcium deficiency will hurt the shells. They will become thin, eventually losing their color as they erode. Calcium deficiencies are even more dangerous for baby snails. Not only will they grow vulnerable shells, but they are just as likely to die in the absence of sufficient calcium levels.

4. There is Coralline Algae on the Snail’s Shell

Do you have coralline algae in your tank? Generally, it is a red algae with branched formations that can be found in thousands of species. It comes in a variety of colors, including white. You have to keep two things in mind where coralline algae are concerned.

First of all, it can live on the shells of snails.[4] In fact, one of the ways of introducing coralline algae to a tank is to add a snail whose shell is crusted with the stuff. Secondly, the algae require stable parameters to thrive.

Coralline algae can turn white as a consequence of sudden temperature swings or light shock. In other words, before you panic in response to your snail’s change in color, you should first ensure that the creature has actually changed color. 

In some cases, the snail’s shell is perfectly fine, and the only thing that has changed color is the algae crusting its surface. In this case, it is common to see Coralline Algae growing on other surfaces, such as rocks and decorations.

5. The Water pH is too Low

Snails do not like soft water; they prefer hard water instead. Water that is too soft and acidic will eat into their shell, eroding it. Pay close attention to the pH, which shouldn’t fall below 7.0. A low pH can also erode a snail’s shell, which will turn white during this period.

6. High CO2 and Potassium Levels 

Some aquarists have noticed that the shells of their snails have turned white due to a high concentration of CO2. The color change is a sign that the shell is eroding. Similar results have been noted in situations where the potassium is too high. This reduces the rate at which calcium is absorbed, compromising the shell’s integrity in the process.

7. The Snail was Exposed to Copper

Copper is toxic to snails. You can introduce it to your tank via tap water, decorative stones, and bacterial treatments, to mention but a few.[5] Eventually, the metal will accumulate upon the snail’s shell, whitening it in the process.

8. The Snail Got Old

Some snails have shells that turn white as they get older. This is a sign that the shell is eroding because of age. You typically see this phenomenon in ramshorns. If you had your snail for a couple of months now, there is a good chance it has grown old and turned white as a consequence.

How to Treat Snails that Turned White?

Some snails have genetic complications, and you can do nothing to stop them from turning white. This also applies to snails that are aging. However, if your snails are seemingly young and healthy and yet they are turning white, there are ways to treat them, including:

1. Replacing the Water Regularly

If your snails turn white, a water change should be one of the first steps you take. It won’t necessarily reverse the effects of the discoloration, not unless the water was filthy. Instead, a water change will create a conducive environment in the aquarium, encouraging the snail to recover from its current predicament. 

Bear in mind that water changes are not a one time deal. It would be best if you performed them regularly. Otherwise, you will undo any progress the snail makes. As a rule of thumb, I suggest replacing 10-25% of the water every two to four weeks.[6]

2. Improving the Water Hardness

Hardness is a measure of the number of minerals dissolved in the water. Snails require hard water to maintain their health. If your snails are losing their color because their water is too soft, you can make it harder by adding substances like crushed coral and limestone.[7]

Personally, I use the Carib Sea Crushed Coral (link to Amazon). By using that product, I was able to raise the hardness of my water considerably. Also, it helped me to balance the pH in my tank, which was consistently low beforehand.

You can also purchase chemical additives that achieve similar results. Though, many aquarists have a preference for more straightforward solutions like baking soda. But crushed coral and limestone are trendy because they also add calcium to the tank.

Calcium is essential for shell growth. By adding crushed coral and limestone, you can undo some of the damage caused by calcium deficiencies. However, if you have fish in your snail tank, you should remember that products that change the hardness can also affect the pH.

3. Dealing With Copper

As was noted above, copper is terrible for snails. This is why you have to pay close attention to your water sources when you perform water changes. If the pipes in your home have copper, your tap water will add the component to your aquarium.

That is why I recommend keeping a testing kit on hand, such as the Seachem MultiTest Copper Test Kit (link to Amazon). Try testing the water regularly to ensure that the copper concentration doesn’t exceed safe levels (0.10mg per liter). If your aquarium has too much copper, perform a water change (20 to 30 percent), using a different water source.

You can also add an activated carbon block to the tank’s filter, which will absorb the copper.[8] If you prefer a faster solution, there are plenty of commercial products designed specifically to remove copper from water.

4. Using a Water Conditioner

The pH cannot be too low. Otherwise, the water will become acidic and erode your snail’s shell. You can raise the pH by adding baking soda to the water.[9] As was mentioned, crushed coral and dolomite chippings will produce similar results, not to mention commercial chemical additives.

You can also avoid a lot of problems by merely conditioning your water whenever you change it. Use conditioners that will remove not only copper but also chlorine, chloramine, and ammonia. Personally, I’ve been using the Seachem Prime Conditioner (link to Amazon) for years, and I couldn’t be more satisfied.

You can trust these same conditioners to regulate the hardness of your water as well, not to mention keeping your impressively pH stable. A water conditioner is usually the preferred solution since it creates a balanced environment for fish as well.

5. Increasing Calcium Concentrations

If you own snails, then you don’t need anyone to tell you that they need calcium. The easiest way to introduce calcium to a snail that is turning white is through its diet. One of the most prominent sources of calcium is cuttlebone.

Available in powdered form, cuttlebone provides other minerals that your snail needs to thrive. Other calcium sources include limestone and powdered oyster shells. If you have eggshells around the house, they can make all the difference. Bake them for ten minutes to remove the bacteria.

But if you are looking for the easiest solution, it would probably be using the DreamDealsSG Tourmaline Balls (link to Amazon). All you have to do is to scatter those at the bottom of the tank. Over time, these balls will raise the calcium, as well as other minerals.

Don’t neglect your snail’s diet. Calcium is vital to their health. But they cannot survive on calcium alone. Their diet should be balanced to ensure that they have all the nutrients they need to grow and maintain their shells.

6. Improving the Tank’s Conditions

Snails should be kept in tanks with the appropriate parameters. They need temperatures that fall somewhere between 72 degrees and 82 degrees F, a neutral pH, and at least one gallon of water for every 20 snails.[10]

Naturally, the size of the tank will vary depending on the type and size of the snails. But most aquarists require at least 5 gallons of water, which will prevent overcrowding. Generally, overstocking and overcrowding are common causes of stress in snails.

The conditions in the tank will affect the health of your coralline algae. It would help if you maintained stable parameters, especially where the light is concerned. Otherwise, the algae will turn white.

If you found this article useful, here are a few related ones that may also interest you:


If your snail’s shell is turning white, the first step would be testing the water. Start by checking the pH. If it has gone below 7.0, I highly recommend that you perform more regular water changes. It would be best if you also considered a water conditioner, as was mentioned above.

If the water conditions are okay, there is a chance that the snail turned white due to its age. As they grow, snails naturally turn white. In this case, you will also notice that other snails appear perfectly fine. Unfortunately, there is little you can do to reverse the process.


  1. https://www.petco.com/content/petco/PetcoStore/en_US/pet-services/resource-center/caresheets/freshwater-snails.html
  2. https://www.petsnails.co.uk/problems/bad-shell-growth.html
  3. https://vivariumtips.com/why-is-my-garden-snail-shell-turning-white
  4. https://reefhacks.com/coralline-algae-reef-tank/
  5. https://www.petwave.com.au/assets/files/PetWave%20-%20Aquarium%20Snails%20Care%20Sheet.pdf
  6. https://www.petco.com/content/petco/PetcoStore/en_US/pet-services/resource-center/caresheets/freshwater-snails.html
  7. https://pets.thenest.com/ways-increasing-hardness-aquarium-12516.html
  8. https://animals.mom.com/remove-copper-saltwater-aquarium-9119.html
  9. https://www.algone.com/adjust-ph-aquarium
  10. https://www.wikihow.com/Take-Care-of-an-Aquatic-Snail

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