For the purpose of this discussion, the common red-eared slider will be used as a representative animal in describing how to feed aquatic turtles.
What do red-eared sliders eat?
An improper diet is likely the most common cause of health problems in captive turtles and other reptiles.
"Red-eared sliders are typically voracious eaters and are omnivorous, eating both animal and vegetable matter."
Red-eared sliders are typically voracious eaters and are omnivorous, eating both animal protein and vegetable matter. As juveniles, they are mainly carnivorous (eat animal protein) and become more omnivorous as they age. All aquatic turtles eat and swallow with their head under water and will not eat out of the water. To help facilitate optimal cleanliness of their tanks, aquatic turtles can be fed in a separate, small aquarium of warm water. That way, they will soil this water, and not their main aquarium. When feeding turtles, offering a variety of food is important. Changing the types of food fed on a regular basis helps stimulate the turtle to eat and provides nutritional balance.
What are some acceptable animal-based protein foods I can offer my red-eared sliders?
The carnivorous portion of their diet should consist of commercial turtle or fish pellets, as well as a variety of invertebrates and vertebrates. Pelleted foods come in several sizes. Larger pellets tend to float well and are attractive to large turtles, whereas smaller pellets tend to sink quickly and are generally accepted by juveniles and small turtles.
"The carnivorous portion of their diet should consist of commercial turtle or fish pellets, as well as a variety of invertebrates and vertebrates."
Aquatic turtles in the wild eat fish, and "feeder fish" may be purchased from pet stores or bait stores to feed pet turtles. Depending on the size of the turtle, fish such as goldfish, guppies, or minnows may be offered. Feeding live fish can provide your turtle with the mental stimulation and exercise that comes with the challenge of chasing and catching its dinner. Fish also can be a good source of calcium for turtles, as long as they eat the entire fish, bones and all. However, recently feeder fish have been implicated as carriers of parasites and bacteria that can infect the pet turtles that eat them. Therefore, if feeder fish are fed to turtles, they should be offered infrequently. Smelt, mackerel, and other oily fish should be fed sparingly or avoided all together, as their high fat content may upset nutritional balance and lead to vitamin E deficiencies. A predominantly fish diet may also lead to a thiamine (vitamin B1) deficiency, so fish should only be offered as a small portion of aquatic turtles’ diets.
Depending on the size of the turtle, amphibians such as tadpoles and frogs can be offered, as can earthworms, snails, slugs, beetles, grasshoppers, moths, crickets, mealworms, wax worms, and other insects. Feeding wild-caught fish and amphibians is not recommended, as they may contain parasites and other infectious organisms that may affect the turtle.
Raw meat, fish, or chicken from the grocery store does not contain a balance of calcium and phosphorus for a turtle and is not recommended as a food source for turtles. Regardless of the protein source, the carnivorous portion of a turtle’s diet should make up no more than two thirds of the diet of juveniles and about half of the diet of adults.
What types of plant material can I feed my red-eared slider?
The plant portion of the diet should be made up of vegetables, preferably ones that float and can be left in the water for the turtle to nibble on throughout the day. Leftover food should be scooped out of the tank daily to promote proper hygiene. Desirable vegetables to offer include dark leafy greens such as romaine lettuce, collard greens, mustard greens, carrot tops, endive, Swiss chard, kale, parsley, green beans, dandelion greens, turnip greens, and clover. Iceberg or head lettuce should not be fed, as it is comprised mostly of water and contains very little nutritional value.
"The key to feeding turtles is to provide variety, as many turtles get bored and stop eating if they are fed the same foods over and over."
The key to feeding turtles is to provide variety, as many turtles get bored and stop eating if they are fed the same foods over and over. Many red-eared sliders are drawn to the color red, so shredded vitamin-A rich red bell pepper is also good to offer. Safe, non-toxic aquatic plants, such as water hyacinth, water lilies, Elodea, or duckweed, can be placed in the tank. Always check the safety of plants before offering them to your turtle to be sure they are non-toxic.
How often should I feed my red-eared slider?
The frequency of feeding depends on the age and size of your red-eared slider. Smaller or juvenile turtles will eat heartily every day. As they get older, adult turtles may be offered a good-sized portion of food every two or three days.
Do I need to give my red-eared slider vitamins and minerals?
The key to proper nutrition for a red-eared slider is a diverse and varied diet containing a balance of vegetable and animal protein, depending on the pet’s age. Some veterinarians suggest adding a balanced, commercially available multivitamin once per week with an additional source of calcium, such as a calcium block or cuttlebone, twice per week.
What about water?
Aquatic turtles, of course, swim in water and drink all day; therefore, the only water requirement for an aquatic turtle is to keep their tanks clean and at an appropriate temperature. Having a well-functioning filtration system that is cleaned regularly is key to ensuring good water quality.
If you have any other questions about nutrition or care of your red-eared slider, make sure you seek the advice of a veterinarian familiar with turtles. Remember, turtles and other reptiles commonly carry Salmonella bacteria on their skin or in the gastrointestinal tracts, so it is important to always wash your hands thoroughly after feeding, cleaning, or handling turtles.