Cassiopea Xamachana..[AKA] The mangrove upside down jellyfish,Is pretty hardy as far as maintainance and up keep go,I use to keep a few of them with a fine substrate,and soft current,in a 20 high,,You would want to keep by themselves,other tank mates will eat the food before they can get it,but the cool thing about them is they are photosynthetic,so have good lighting on your tank,they will move around the tank so,have the strainers of your powerfilter covered with a large fine foam filter,so if the run into it they can basically jump off of it,You can feed them brine shrimp,If you use other shrimp use small pieces without the shell,and a small piece of fish they will consume....Hope this helped...They don`t live long,the ones you get in the aquarium trade are older....They are very hypnotic to watch ..