What ele can live with a Red-eared slider?

Question
I was wondering what else can live with one of these guys. Is there any kind of frog or fish that can live in an aquatic with a basking area tank. Also i just got the turtle starter kit with the 20 gallon tank and the whisperer filtration system. I am strongly considering getting a heater because i feel the tank might be a little cold. Thank you!!

Answer
Unfortunately, with a starter kit, the turtle itself will quickly become crowded even without cagemates. The guideline for tank size is 10 gallons of water per inch of turtle shell length. A 20 gallon tank usually only has about 15 gallons of water in it, so can only house about 1.5" of turtles.

In a larger tank (about 50% larger than the above rule), you can combine fish that are either fast or armored, or provide good hiding paces. Most other possible tank mates will just be nipped, harassed, or eaten, or will nip, harass, or eat the turtle.

For some great care advice, try http://www.redearslider.com