There are hundreds and hundreds of different species of beetles. The Goliath beetle from Africa grows quite large - 4 1/2 in. long, weighing 100 grams. Caterpillar Hunters, Atlas, Elephant, Hercules also can do well in captivity. As with all creatures, the trick to making them thrive is keeping them in the proper conditions for each one. Research the one you are interested in and set up the enclosure as suggested.