This guide goes over the required equipment, habitat, and basics for taking care of your red-eared slider.
Red-eared Slider – Trachemys scripta elegans
Overview
Red-eared Sliders (RES) are the most commonly sold pet turtle in the United States. These turtles get their name for the red stripe found on the sides of their head. A hardy breed, these turtles can live 20 or more years when properly cared for in captivity. However, RES grow quite large as adults: the average adult male grows to 7-9”, and the average adult female grows to 9-12”. At adulthood, these turtles require large enclosures, and therefore can be expensive turtles in the long run.
Community Environment
RES do not do well in captivity when kept together. As they become adults, they tend to become quite territorial and aggressive. RES should generally be kept alone in most captive environments. If you want to keep RES in a communal environment, you are going to need a large enclosure or pond.
Equipment
- Aquarium (at least 10 gallons for every inch of shell)
- Canister Filter (with filtration capacity at least 3x the size of aquarium as turtles are messy)
- Basking Light
- UVB Bulb (combination basking/UVB bulbs are available – these are Mercury Vapor Bulbs)
- Basking Spot
Aquarium/Enclosure
For all species of semi-aquatic turtle, the rule of thumb is to have 10 gallons of water for each inch of shell length.
Red-eared sliders grow to large sizes as adults, and therefore I advise that you buy a big tank early on to save money in the long run. With younger RES, a 55 gallon aquarium is acceptable. As they are approaching adulthood, a 75 gallon (preferably larger) aquarium is the minimum for males, while females will almost certainly need a 125 gallon aquarium.
For larger sliders, it is often more cost-effective to setup a plastic stock tank (100 gallons or more) than it is to buy a glass aquarium. It is also common for slider owners
Heater
Hatchling RES require water temperatures of 75-80 degrees F, while yearlings and older should have a water temperature from 72-75 degrees F. To get these temperatures consistently, it is required to use a water heater. I have had the best luck with the Aqueon Pro Water heaters, and recommend them based on your aquarium size:
40-55G: 100 or 150W Aqueon Pro Water Heater
55-75G: 200W Aqueon Pro Water Heater
75-100G: 300W Aqueon Pro Water Heater
There are cheaper heaters available, but I do not like to use glass-enclosed water heaters due to the shatter risk from a turtle ramming it. In addition, if your environment is colder than average, you may need a slightly more powerful heater than I have recommended above.
Above this size, you will need to have multiple water heaters. For example, I have seen two 200W Aqueon Pro Heaters used in a 125G setup.
Filter:
Turtles are very dirty creatures. Usually aquarium filters are rated for the size of aquarium, but do not take into account the increased waste produced by a turtle. The most cost-effective option for a turtle keeper is to get a canister filter. These filters sit underneath your aquarium stand, and have tubing that connects to the intake and output that will be placed over the edge of your tank.
When purchasing a canister filter, aim for a filter that is able to handle a capacity per hour three times that of the size of your tank. For example, a 55G turtle aquarium should have a filter that can do at least 165GPH (gallons per hour) of filtration. You must also test the filter (especially with smaller turtles) to ensure that it does not provide too much suction that the turtle cannot swim away from it.
For those on a budget, I suggest looking at the SunSun Canister Filters, specifically the HW302, which is rated up to 265GPH, and could be used with up to a 55G aquarium with just one turtle. They also produce filters for larger aquariums.
If you’re looking for the best filter for your setup, I’d recommend the adjustable Fluval 407, which can do up to 383GPH. Above this, take a look at Fluval’s FX4 series, which goes up to 700GPH.
There are many brands of canister filter out there, but these are two brands that I’ve found fit most needs.
Thermometer:
You will also need a water thermometer to check the temperature of your water. Do not rely on the built-in thermostat on your heater, as they tend to be poorly calibrated. I’ve had great luck with the Zacro aquarium thermometer. Whatever you purchase, I’d recommend getting a digital thermometer for ease of use.
Basking Light and UVB Bulb:
RES require a basking spot with a temperature around 90 degrees F. They also require UVB rays in order to help them synthesize Vitamin D3. There are two options here:
- Purchase a mercury-vapor bulb that produces both Heat and UVB in one fixture.
- Purchase a basking bulb AND a UVB Bulb and place them in separate fixtures.
I have found that, over time, it is cheaper to have the UVB and Basking bulb separate. However, many prefer one bulb for convenience.
There are keepers who do not provide UVB via a bulb, and instead other provide their turtle time outside or supplement Vitamin D3. I personally find it easier to simply provide a UVB bulb in their environment.
Word of warning: Stay away from off-brand bulbs. Without a UVB meter ($$$), it’s nearly impossible to know if a bulb is effective at emitting UVB. The main brands (ZooMed an ExoTerra are two I personally use) tend to be more consistent in quality.
Basking Spot
When your turtle is small, there are commercially available basking docks that work well. Commonly used are the ZooMed floating dock and this PennPlax floating basking platform.
As your turtle enters adulthood, the only commercial available option I am aware of is the PennPlax above-tank basking area. This is a great product, however many people simply make their own above tank basking area using egg crate ceiling tile material.
Food
Red-eared sliders are omnivorous, meaning they eat both meat and vegetables. However, younger turtles require more protein as they are growing. Therefore, what to feed and how much to feed a red-eared slider is determined by its age.
Hatchling to Six Months Old
At this age, RES should be offered as many pellets as would fit in their head once daily. You can also begin to introduce greens (mustard greens and collard greens are a good start).
Six Months and Beyond
At this point, we are going to move from feeding the turtle daily pellets towards getting them on a stable, yet varied, diet for the rest of their lives. These turtles should be offered a variety greens daily. However, they should only be offered the commercial pellets three times weekly, and just as much as fits in their head.
You may need to slowly taper them off of the feeding schedule they had as hatchlings, but many will adapt quickly to the new feeding schedule.
When choosing a turtle diet, one important thing to consider is the Calcium to Phosphorus ratio (Ca:P). While both are important to a turtle’s development, it’s important that we do not allow the turtle to have a diet where they would become deficient in calcium. Aim for a pellet that, overall, gets them to around a 2:1 Ca:P ratio.
Personally, I have fed these pellets with good success:
There are other pellets on the market, but I have not been impressed with their content of vitamins, protein, or their Ca:P ratio.
Quick note on vegetables: Turtles will often try and beg for pellets. Imagine the turtle seeing the pellets as dessert – make sure they’re getting veggies as well!
References and Further Reading:
Divers, S. J., & Stahl, S. J. (2019). Mader’s Reptile and Amphibian Medicine and Surgery. St. Louis, MO: Elsevier.
Notes: This book is a great resource on the treatment of turtles, tortoises, and other reptiles. While not a must-have for the average keeper, I have found it a great resource that goes into detail of the anatomy and care of turtles.
MacArthur, S., Meyer, J., & Wilkinson, R. (2004). Medicine and Surgery of Tortoises and Turtles. Oxford: Blackwell Publ.
Notes: This book has a more specific focus on the care and medical issues regarding tortoises and turtles. If you have a large interest specifically in the care of turtles, this book would be a great resource for you.