Expenses include the aquarium, hood and light, heater, filter, gravel, water treatment, cleaning supplies, and of course, the fish. Take a checklist and go online or to a pet store, then write down the costs for all the items you are interested in. Sit down and determine what your bottom line is before you make your decision.

If your budget is very tight, make a list of what you need and let your friends and family know that you'd like items from that list for your birthday, graduation, or Christmas gift.

That way you can get started without having to opt for inferior equipment and supplies.

Size
Size includes the fish, aquarium they are kept in, and the location to place the aquarium. Avoid tanks under 10 gallons if you are a first time aquarium owner. Small aquariums are actually more difficult to manage than larger ones, as toxins can build up very quickly in the small volume of water. Temperature changes and water chemistry changes can also occur very quickly when there are only a few gallons of water.

Be aware that an aquarium larger than 15 gallons will weigh over two hundred pounds when filled, and should be placed on a stand rather than a shelf or desk. You'll also need a place to put the aquarium that is not in direct sunlight, or be subjected to drafts or temperature extremes that could harm the fish. The location must also be capable of getting wet from time to time. Performing maintenance, adding or removing fish and other items from the tank will splash water around the tank. so keep that in mind of you are thinking about keeping a tank on your desktop.

Lastly, be realistic about the size and number of fish you wish to keep. They will determine the size of aquarium needed, which ultimately impacts the space you'll need to accommodate it. Start with a few small easy to care for fish. As you gain experience, you can move on to bigger and more challenging fish.