Hardy? No. They are not a long lived chameleon to begin with, and when something goes wrong there is not much you can do. You could keep a trio in a 10 gallon tank, but a 20 would be better and you could probably keep 6 just fine with 1 male and the rest females. They eat 1/4 " crickets as adults and flies, and some will eat other small insect items. If you go to my website in my signature I have instructions for creating a tank.