Here is info from a fishbook I have.
-Temp-68-79 f
-Length-3 ½ inches
-Territorial yet peaceful when combined with fish that perfer middle of tank.
-eats live foods,algae
- The fish will be healthier if 1 to 2 tablespoons of salt is added per 2 ½ gallons
The ones I see are 2 inches in the store and bickering amongst each other, but not the other fish.