Turtle Tank Calculator

in
Measure from front to back of the shell.
Biology

Calculate the minimum recommended aquarium size for a pet turtle based on shell length.

Formula

Min gallons = shell length (in) × 10 per turtle; +50% per additional turtle
  • Rule of thumb: 10 gallons of water per 1 inch of shell length for aquatic turtles.
  • Water depth should be at least 1.5× the turtle's shell width.
  • At least 25% of the tank surface should be dry basking area.

6-inch shell, 1 turtle

Inputs
  • Shell Length (Carapace): 6 in
  • Number of Turtles: 1

6 × 10 = 60 gallon minimum tank.

Frequently asked questions

What is the rule for turtle tank size?
The standard rule is 10 gallons per inch of shell length. Bigger is always better.
Do box turtles need water?
Box turtles are semi-terrestrial and need a shallow water dish rather than a full aquarium.