Red-eared Sliders

Question
We have two RES turtles in a 40-gallon tank, with 5" of water. Now 1 1/2 years old...each is the size of a hockey puck. We've noticed that at times, one specific turtle snaps and bits at the other. Is this normal behavior as playful action, or is there a problem? (under-feed?...territorial issue?)

Answer
Territorial issues. Red-ear Sliders are generally not good at sharing. The most common recommendation would be to offer 10 gallons of water per inch of shell length.

I notice you said 5" of water. A 40 gallon tank is 16" deep, so you are about 1/3rd filled, or about 12'ish gallons of water, or enough for about 1-2" of turtles, and I bet your guys are at least 2-3" long each.

You can gain some benefit quickly by filling it close to full- be sure to leave a full 'turtle length' between the top rim and any thing they can climb on or the top of the water.

In the wild, Red-ear Sliders (and many other turtles) do not hang out with other turtles unless they are basking or mating. In captivity, one will almost always bully the other(s) unless each has its own hiding places, basking choices, etc. This means either a lot of space, or keeping them in separate habitats.

Good luck, and give http://www.redearslider.com and http://www.turtleforu.com for more ideas.