What Are The Required Vitamins For Red-Eared Sliders?

Required Vitamins For Red-Eared Sliders

The information is current and up-to-date in accordance with the latest veterinarian research.

Sharing is caring!

Just like humans, turtles also need vitamins. Even if you give your turtles the perfect diet, they might experience vitamin deficiency. A few days earlier, one of my friends told me that the vet told him his red-eared slider is lacking vitamins. So, I thought it would be great if I can list down all the necessary vitamins that have important roles to play in the body of the red-eared slider. 

The required vitamins for red eared slider are:

  • Vitamin A
  • Vitamin D3
  • Calcium
  • Phosphorus

Generally speaking, if you are providing a fairly-diverse diet to your red-eared slider, it will get all the necessary vitamins from this food. But, the two major vitamins that your red-eared slider needs are, Vitamin A and Vitamin D.

Other than these two, there are other supplements that you might need to add to your red-eared slider’s diet. However, most of these supplements should be added as per the vet’s advice.  

Vitamin A: 

From my experience of taking care of pet turtles, if you need to add supplements to your red-eared slider’s diet, it is probably going to be vitamins A. There are many health issues that the lack of vitamin A can cause. Such as: 

  • Vision problem 
  • Hypovitaminosis A 
  • Upper respiratory disease 
  • Aural and ear abscesses 
  • Squamous metaplasia (This condition thickens the duct lining of pancreas and kidney)

The first two are very common among the red-eared sliders. The most serious are vision problems and other health issues related to it. Lack of vitamin A in your turtle’s diet can lead to red, swollen and puffy eyes. If you do not take measures to correct this deficiency then it can lead to blindness.

Moreover, vision problems can also be a result of hypovitaminosis A. The symptoms include: 

  • Continuous runny nose 
  • Infection in the respiratory tract 
  • Visible ulcers, peeling and raw skin 
  • Loss of appetite 
  • Egg embryo deformities in female red-eared sliders 

Vitamin D: 

The second most important vitamin for your red-eared slider is vitamin D, or to be precise vitamin D3. The turtle produces vitamin D3 by the pigment cells located in its skin as well as on the shell when it comes in contact with the UV light (both natural and artificial). This vitamin helps the red-eared sliders to use the calcium to promote healthy shell, bones, skin and more. 

When the red-eared slider suffers from vitamin D deficiency, it is unable to metabolize the calcium and as a result, it suffers from bone diseases. However, from my experience, I can tell, your turtle does not require vitamin D supplements daily. The best way to make sure your slider gets enough vitamin D3 is to let it soak up in natural light i.e. unfiltered sunlight. 

I would recommend that your red-eared slider should sunbathe at least twice or thrice a week for 30 to 40 minutes. For the safety of your turtle, make sure the area around is free from predators. 

Nevertheless, in certain cases, the red-eared slider might need D3 supplements. During winter, if you are unable to provide sunbathe to your pet then, occasional D3 supplements are alright. 

Pet Turtle Diet & Feeding Chart

Pet Turtle Diet Feeding Chart

For a printable version of this amazing diet chart, click here!


Calcium is one of the very important minerals for your red-eared slider. Most of the turtles receive the required amount of calcium along with vitamin D. But, captive red-sliders often suffer from calcium deficiency than the ones in wild. 

Many turtle owners believe that their pets are getting enough calcium from their diet. In my experience, these people are not providing their turtles with enough calcium-rich foods. The sliders show the following symptoms when they suffer from calcium deficiency: 

  • Wobbly walking or awkward swimming 
  • Lack of appetite
  • The pyramiding shell of the turtle (The scutes develop different than usual and it resembles pyramid) 
  • Soft or rubbery shell 
  • Lumps on the head or swollen body parts 

Calcium-deprived red-eared slider develops anorexia. This happens because the turtle does not only need calcium for bones and shells but also for proper muscle contact. As a result, without enough calcium, the muscle, as well as the digestive system, slows down which results in anorexia. 

Calcium deficiency is one of the leading problems among most red-eared sliders. I have seen pet owners provide their turtles with calcium-rich supplements and foods thinking they will not suffer from metabolic bone diseases.

If it is unable to metabolize the calcium, then the problem will arise. Therefore make sure, your red-eared slider gets adequate calcium, proper Vitamin D3 and also maintains the right calcium to phosphorus ratio. 


Just like calcium, phosphorus plays a huge role in your red-eared slider body. Phosphorus, calcium and Vitamin D3 together play an important role in building the bone, muscle, and shell. So, it is important to maintain a good Ca: P ratio in your slider’s diet. The proper diet of the red-eared slider should contain Calcium and Phosphorus ration of 1:1 to 2:1. 

But, phosphorus is available in most of the foods that your slider eats. Hence, you should give more attention to its calcium intake. 

Vitamin and Mineral Supplements for Red-Eared Sliders: 

If your red-eared slider is not getting proper vitamin or minerals from its diet then, there are some commercial supplements that you can add. The following are the supplements that you can give to your red-eared slider in case of vitamin A, vitamin D3, phosphorus, and calcium deficiency: 

  • Cuttlebone: This is used by most turtle keepers. This is inexpensive and easy to find. Just remove the hard back part and break it to chew sized pieces. You can find it easily in any pet store. This is my favorite cuttlebone for turtles. You’ll find packs of 3 cuttlebones that’ll last you a long time.
  • Rep-Cal Calcium: This supplement is phosphorus-free and does not contain vitamin D3. This supplement is not necessary if your turtle gets enough to sunbathe. Click here to check the latest price on Amazon.
  • Rep-Cal Calcium infused with D3: This supplement is available in powder form and contains no phosphorus. The D3 in the supplement will help the indoor turtles to metabolize calcium in its body. Click here to check the latest price on Amazon.
  • Rep-Cal Herptivite Multivitamin (Amino Acids, Vitamin A): It contains beta-carotene that allows the turtle to easily convert it into Vitamin A. Click here to check the latest price on Amazon.
  • Tetra Fauna ReptoCal (Vitamin D3, Calcium): A powdered combination of Vitamin D3 and calcium with a trace amount of phosphorus. Click here to check the latest price on Amazon.  
  • Zoo Med’s Reptivite (Amino Acids, Calcium): This contains Ca: P to the ratio of 2:1. This is a powdered supplement, great if your red-eared slider is suffering from calcium deficiency. Click here to check the latest price on Amazon.  
  • Cod Liver Oil (Vitamin A): Cod liver oil is soft-gel like supplement available in supermarkets, health stores, and pharmacies. Just like other fish oils, this oil is rich in vitamin A. This is unnecessary for healthy red-eared sliders but a suitable choice for the ones suffering from Vitamin A deficiency. 


I hope you got an idea about the essential vitamins and minerals for your red-eared slider. I recommend the turtle owners to see a vet before adding any commercial supplement to their turtle’s diet.

If you give your red-eared slider a proper diet with vitamin and mineral-rich vegetables, then you might not even need to use any of the supplements ever. 

Sharing is caring!

About Author

Muntaseer Rahman started keeping pet turtles back in 2013. He also owns the largest Turtle & Tortoise Facebook community in Bangladesh. These days he is mostly active on Facebook.


This site is owned and operated by Muntaseer Rahman. TheTurtleHub.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. This site also participates in other affiliate programs and is compensated for referring traffic and business to these companies.