Tank size: Allow at least 10 gallons of water per inch of shell (e.g. a 10 slider 100 gallons). Many experts recommend 75100+ gallons for one adult. Bigger is always better: Chewy notes a tank should let your turtle swim 45 body lengths before turning around.
Dont worry, Im here to promise you that figuring out what size tank for red eared slider you need doesnt have to be confusing. In this complete guide, well walk through everything together.

Proper tank size plays a key role in your turtles health and well-being. The ideal tank size for a red-eared slider is at least 75 gallons for one adult turtle. Larger tanks are recommended for multiple turtles to ensure they have enough space to swim, bask, and move freely.

To save you money in the long run, its best to buy an adult-sized enclosure right off the bat, even if your new pet red eared slider is just 4 long. Since most red-eared sliders top out between 8-11, ReptiFiles recommends 100 US gallons (379 liters) as the minimum acceptable red-eared slider tank size.
dult red-eared sliders, which can reach up to 12-14 inches (30-35 cm) in length, require an even larger tank, ideally 75 gallons (280 liters) or more per slider.