Setting Up Your First Aquarium

A step-by-step approach to a first freshwater aquarium: planning, assembling equipment, rinsing and filling, and cycling the tank before adding fish.

Planning

Gathering materials and starting the process typically takes one to two weeks. Larger aquariums are generally preferred because more water volume dilutes the toxic waste produced by fish and allows a more forgiving margin for error. Choose the tank, stand, and equipment before buying any livestock.

Choosing a location

Place the tank on a hard, flat, waterproof surface or a dedicated stand. Avoid direct sunlight, air conditioning or heating vents, and doorways with drafts. Position it near an electrical outlet and within reach of a water source and drain to make maintenance practical.

Equipment list

• Aquarium of 10 gallons (about 38 litres) or larger
• Heater sized to the volume (roughly 5 watts per gallon for a 10 °F / ~5.5 °C rise)
• Filter (a sponge filter is simple for beginners)
• LED light with a timer if keeping live plants
• Substrate (gravel, sand, or plant substrate) and decorations
• Lid, thermometer, water conditioner, test strips, and a siphon

Rinsing and assembly

Rinse the substrate and decorations in water to prevent cloudy water once the tank is filled. Place the tank on its stand, add the rinsed substrate, then install the filter, heater, and decorations. Plant live plants at this stage if they are being used.

Filling the tank

Fill the aquarium with room-temperature water treated with a water conditioner. Tap water often contains chloramine, which is harmful to fish and does not evaporate readily, so conditioning the water is essential. After installing the lid and light, allow the heater 20 to 30 minutes to acclimate before powering it on, and wait about 24 hours to check for leaks.

Cycling before fish

A new tank lacks the beneficial bacteria needed to process fish waste, so it must be cycled before stocking. The nitrogen cycle establishes bacteria and plants that convert toxic ammonia into nitrite and then nitrate. Cycling commonly takes about four to six weeks. It can be accelerated by transferring used filter media or substrate from an established tank, or by adding live nitrifying bacteria.

Monitoring the cycle

Test the water every day or two during cycling. Perform a partial water change whenever ammonia or nitrite is detectable above 0.2 ppm. The cycle is considered established once ammonia and nitrite read 0 ppm, nitrate is detectable, and the tank can handle normal feeding without a rise in ammonia or nitrite.