When selecting a new aquarium consider the application you intend to use it for. Is it intended for marine or a freshwater use? Will it be a reef tank or live-plant tank? Remember good stocking practices and plan ahead. Instead of setting up the aquarium and then selecting what animals will go into it, plan the entire aquarium around the aquatic life you want and you'll be sure of success! Consider these rules for stocking an aquarium when choosing what size of aquarium you'll need:
Freshwater: Roughly 1" of fish per gallon of water. More accurately, 1" of fish for every twelve square inches of surface area.
Saltwater: 3" of fish per square foot of surface area. If the cost of the aquarium you'll need to house the animals you want will exceed your budget, eliminate some of the animals you want! If you try to keep too many fish in an aquarium, you'll spend a lot more money replacing fish and solving problems than if you had purchased a larger tank in the first place.
Remember that the larger an aquarium is, the EASIER it is to maintain. This may sound like a contradiction until you think about it for a minute or two. It is harder to pollute a lake than a pond. The larger the volume of water, the greater the ability of the water to cleanse itself through oxidation and reduction. Take it from a company that maintains aquariums for a living. It takes us just as long to clean an over-stocked thirty gallon aquarium as it does to clean a properly-stocked 100 gallon aquarium.
