I have cared for over the years many types of crocodillians, Alligators caiman crocs etc. None of them are good for tanks, A smooth front or dwarf caiman can still break 3 inchs of glass with a good tail slap or with their heads. As someone said they are best kept outdoors weather permiting. They do require a lot of space more than you think. I had a whole room for one caiman. It was still not enough room for him. Also feeding these kinds of animals can get very expensive, Its not like having fish or a snake you have to provide a varied diet. They dont make food for crocodillians that you can buy at the local pet store. I was buying about 100 dollars every two weeks of seafood and feeder fish. Also the lighting requirements were also costly. Because you need such a large enclosure you may need up to or more than 2000 watts or light plus a heater for 400 gals or more of water. Not to mention the risk you take as an owner. Someone i know has one less arm from his pet. He has a 14ft cuban croc that tore off his arm at the elbow, because he wasent on top of his game that day, he learned his lesson on playing with stuff that can seriously hurt you. This goes for caimans too, even though they are little compared to other crocs.