The Basics:

An attractive and hardy animal, the Red-Eared Slider has traditionally ranked among the most popular pets. Unfortunately, inexperienced keepers sometimes make the mistake of thinking that this is a "simple" pet to care for, which results in a needlessly short lifespan for the turtle. Although not overly demanding, the Red-Eared Slider does require a commitment on the part of its owner. If cared for
properly, this turtle can live for over 25 years. There are reports of some specimens living past 40. Relatively large turtles, they typically are 8-10 inches long, but some can reach 12 inches. Males are smaller than females, and have longer thicker tails. Most Red-Eared Sliders have the trademark reddish/brown stripe of their eyes, but some do not exhibit these markings. When young, they have a green shell, but it darkens with age. Diurnal animals, Red-Eared Sliders are active during the day. In nature, they sleep in the water at
night, either at the bottom or floating at the surface.

Enclosure:
They Need A  Lot of Swimming Space :

The web-footed Red-Eared Slider is an excellent swimmer. So, it needs a lot of space to paddle through the water. It also needs to have constant access to a dry basking area. A single Red-Eared Slider should have at least a 100-gallon aquarium, and a pair a 125-gallon tank. Between one half and two thirds of the tank should be filled with chlorine-free water. This water should range in depth from 2-3 inches at its shallowest point to 1.5 to 2 times the turtle's body length at its deepest. So a 5-inch young turtle should have water that's 7.5-10 inches deep at its deepest point, and a 10-inch adult should have a maximum water depth of 15-20 inches. There must be enough space between the water surface and the top of the tank to prevent the turtle from escaping. The enclosure must also have a secure tight-fitting screened lid. Although
they're great swimmers, Red-Eared Sliders will never win a gold medal for climbing, so a sloped surface must be included in the enclosure to help the move from water to dry land.
Any combination of smooth aquarium rock, Plexiglas ramps, anchored cork and logs can be used to create this slope. It's also a good idea to have anchored cork or log platforms in
the middle of the wet area that turtles can use as resting spots. Rough rocks must not be used, since they can scratch shells, opening the way for bacterial infections. The dry land section of the enclosure should have smooth rocks, and commercially available driftwood for basking spots. Non-toxic live or artificial plants should be provided to enhance the turtle's sense of security.

Substrate:
Slate and Smooth Rocks Work Well:

Red-Eared Sliders have relatively simple substrate needs. Slate, smooth rocks or gravel that is too large to fit in the turtle's mouth make good substrate choices. Substrates must be inspected daily, so soiled material can be removed.

Temperature:
They Must Be Able To Bask:

Ambient air temperatures in the enclosure should range between 75 and 80 degrees Fahrenheit and water temperature should be between 72 and 76 degrees. When not in the water, Red Eared Sliders spend a
great deal of time basking, so their enclosure must offer a spacious, dry basking spot with a temperature of 85-90 degrees Fahrenheit. This can be created through the use of a supplemental external basking lamp positioned over the tank's tightly fitting screen top. Follow manufacturer's directions carefully when using the lamp and use a timer to avoid overheating the enclosure. Nighttime temperatures should be in the low 70;s. Temperatures can be maintained through the use of under tank heat pads and water heaters (again, follow manufacturer's directions). Heat sources should be controlled by a thermostat or rheostat. Never guess the temperature. Install thermometers in the water, near the drying area surface and in the basking area. Important - see the Note About Day/Night Light Cycles and Heating below.

Lighting:
UVB Exposure Is Essential:

Red-Eared Sliders must be exposed to UVB light 12
hours a day. This should be provided by a reptile fluorescent lamp designed specifically for terrarium use that emits UVB rays. The fluorescent bulb should be replaced every six
months. Glass blocks out UVB light, so overhead light sources should be kept behind a wire mesh cover, not a glass or acrylic tank top. Exposure to UVB is necessary, if the
turtle is to receive the amount of vitamin D needed for the metabolism of calcium, which is essential to the development of a healthy skeletal system, including the shell. Important - see the Note About Day/Night Light Cycles and Heating below.

Note About Day/Night Light Cycles and Heating:

All reptiles, including this pet, must have distinct day and night periods in their enclosure to maintain their biological rhythms. (See the lighting entry above for the specific length of this animal’s day/night cycle.) The day period must be light; and night must be dark. A timer should be used to set day/night periods. If a heat source is required to maintain correct nighttime temperatures, use heat mats or strips mounted below or on the side of the tank, infrared heat lamps, ceramic heat emitters, or a combination of these products. This will allow the enclosure to be heated while remaining dark. Follow directions carefully with all products. If ceramic heat emitters are used always choose fixtures with porcelain or ceramic sockets and to protect against fires do not place them by dry wood or flammable fabrics. Ceramic heat emitters must be kept out of the reach of children and all pets, including dogs and cats.

Diet:
Young Turtles And Adults Have Different Food Requirements:

Animal matter should make up 40% to 50% of the diet for an adult and 50% to 60% for a very young Red-Eared Slider. Adults should be fed 2-3 times a week, while youngsters (under six months) should be given food once a day to every other day. Avoid giving adults too much protein. Good foods include leafy lettuces, mustard greens, dandelion, carrots, zucchini, turnip greens, and aquatic vegetation such as water hyacinth and water lettuce. Aquatic insects and feeder fish, such as guppies, aquatic snails and silkworms, can also be offered, as can commercially prepared turtle food. Like people, Red-Eared Sliders do best when they eat a variety of nutritious foods. Offer only as much as the turtle can consume in one feeding session. Remove any uneaten food from the enclosure. Important -- It is necessary to provide calcium and vitamin supplements as part of the diet. Please read the supplement section below:

This pet eats plant and animal matter. The insects offered to it should be dusted with a plain calcium supplement. Either the insects or plant matter offered to it should also be dusted with vitamin supplements. As a rule, a growing juvenile's food should be dusted more often than an adult's. Follow product label directions when applying supplements, and avoid over-supplementing food.

Water & Humidity:

The Red-Eared Slider will drink water while it swims. This makes it essential to maintain clean water in its enclosure. Water must be cleaned daily to remove waste and uneaten food. About 25-percent of the water in the enclosure should be siphoned out and replaced every week. Depending on the size and "neatness" of the turtle, the water should be drained completely and replaced every month or two. When
replacing water, make sure it is close to the same temperature as the water currently in the tank. Clean filtered water, free of chlorine and heavy metals should always be used in a Red-Eared Slider's enclosure.A canister filter should be installed in the tank to keep the water clean. Water changes must still be made, even if a canister is used.