How Big Do Pet Turtles Grow?

Sure, that little baby turtle in the aquarium is cute, but he is going to get much larger and require 10, 20 or 40 years of care and maintenance. Many of the most common pet species of turtle reach mature sizes varying between a couple inches long and over 20 inches long.

  1. Why Size Matters

    • A turtle's mature size will dictate the minimum enclosure size, which could very well dictate whether or not you have the space to care for him. The size and species can also determine how much care is involved. For example, a large slider needs a water area deep enough for him to dive and swim in, as well as being at least one and a half times longer than his shell. A small, 5-inch mud turtle, on the other hand, isn't as fond of swimming and needs a small land area with a water area deep enough to cover his shell plus a few inches. Larger turtles are also harder to handle. Cleaning and filtering a large water area can become time-consuming and expensive; land-dwellers need appropriate substrate and natural decorations.

    Sliders and Painted Turtles

    • Several slider species and subspecies are common in the pet trade, but the red-eared slider is one of the most common pets worldwide. Red-eared sliders can grow up to 11 inches long, which is similar in size to some other turtles. The closely related Florida cooter can reach up to 16 inches. His size isn't the only factor that determines his tank size, though. Because of their basking habits and need to swim around, these turtles need a large tank with a separate water area and basking area. Painted turtles, as their name suggests, are quite colorful. Paints grow to between 7 and 10 inches; like many other species, the female painted turtle is noticeably larger than the male. Paints also need a large enclosure due to their basking and sleeping habits: these guys like to sleep in the water or on half-submerged structures.

    Mud and Musk Turtles

    • Much smaller than the basking turtles, pet mud and musk turtles rarely exceed 5 inches. Their shells are steeply sided and almost give a sharp appearance. They can live in much smaller habitats than the larger pond turtles, although they do have some different needs. Mud turtles are at home both on land and in water, so they need an actual land area to explore as opposed to a simple basking site. Both types feed along the bottom and will eagerly take shelter in upside-down flower pots, hollow logs or other underwater structures.

    Box Turtles

    • Semi-large, tortoiselike box turtles are common in the pet trade and are quite a bit different from many of the other common types. These turtles have high, domelike shells as opposed to flat carapaces and they live on land. Depending on the species, pet box turtles can grow anywhere from 6 inches to over 2 feet, although 6 to 12 inches is more common.