Tank

Tank is the first major consideration when setting up an aquarium -- its size, shape, material, and location. The size of the tank will not only be based on the number of fish you want to keep or the amount of space you have for an aquarium, but also on amount of work you can put into maintenance. Contrary to common belief, a smaller tank does not necessarily mean lesser amount of maintenance. Since a smaller tank contains smaller volume of water, the smallest changes in water chemistry can have significant impact on your fish. The bigger the aquarium, the more it is able to withstand changes in temperature and water chemistry. For beginner aquarists, a medium-sized tank of at least 120 liters is a good starting point. Go for standard-shaped tanks (rectangular or square) as they easier to set up with lights and other equipment. Avoid using a deep tank as well since they are harder to clean and don't allow for even distribution of light.

Tank Stand

It should be strong enough to carry the weight of a water-filled aquarium and all its equipment. The surface should be flat and even. Aquariums that stand on uneven surfaces tend to leak and crack easily.

Filter and Filtration Equipment

The number of options for filter can be overwhelming. Basically, your choice will be determined by the type of tank you have and by your budget

Lighting

Most fish have a biological rhythm that is based on dusk and dawn. Integrating timer-regulated lighting into your aquarium is the best way to create a semblance of this rhythm. The right amount of light is also of prime importance towards maintaining aquarium ecology. Excessive lighting promotes algae growth, which is why most aquarists go for fluorescent bulbs over incandescent bulbs as they do not emit too much heat.

Heater and Thermometer

Unstable water temperature stresses fish, making them more susceptible to disease. A good aquarium heater helps stabilize water temperature.