Maintaining a tropical fish aquarium is a fun and rewarding hobby. It can also be quite challenging because there is so much to know. The first thing to figure out, is whether you want a saltwater or freshwater aquarium. The equipment needed for each is quite different. There are also many different methods for each type, and you have to figure out what works best for you. I have tried many different methods, to different degrees of success. I have gone to the extremes - ultra high-tech tanks with state of the art equipment, probes monitoring everything, data logging, automatic dosing - you name it. Once set up, you pretty much just watch the show and it takes care of the rest. On the other hand, I've had natural tanks, with no filter, no lights, etc. Perfectly balanced, with very few small bodied freshwater fish, and loads of water scrubbing plants, fed by natural sunlight, to naturally clean the tank. Both were successful. Was either better than the other? Not really. In fact, I'm not a fan of either method. My personal preference is somewhere in the middle. I like to tinker and toy with my tanks, I like to maintain them - I don't need every last thing taken care of for me by some ultra intelligent robo-tank. On the other hand, the natural tanks were severely limited on stocking levels due to the lack of real filtration. I recommend starting somewhere in the middle, and as you learn more about the hobby, you'll develop your own preferences as well. There's a lot of great information on setting up an aquarium here: http://www.tropicalfishtalk.com