How to Start an Aquarium Tank

Choose a place in your home for the aquarium. The spot should be away from direct sunlight to prevent algae growth and near an electrical outlet for a convenient power source. Make sure the stand or piece of furniture the aquarium will rest on can support the weight of a full tank. If in doubt, choose another spot.

Cut the sheet of cork slightly larger than the footprint of the aquarium and place onto the stand or furniture. Set the empty aquarium on top of the cork.

Choose the method of filtration you'll use. Biological filtration employs beneficial bacteria inside the tank to neutralize harmful chemicals by means of an undergravel filter. Mechanical/chemical filtration uses an external box filter that sweeps water through a layer of activated charcoal, trapping particles and eliminating chemicals. Biological filtration is suitable for most small to moderate-sized freshwater aquariums; mechanical/chemical filtration is more powerful and better suited for large aquariums.

Set up the undergravel filter, if you're using the biological filtration method, by laying the plastic filter sheet flat on the floor of the tank with the two vertical airtubes at the back (airtubes help to circulate the water through the filter). Models by different manufacturers vary, but most undergravel filters utilize airstones (porous stones attached to airtubes) to disperse oxygen and push water through the filter. Assemble the undergravel filter according to the package directions.

Set up the exterior box filter by inserting the filtering medium (activated charcoal, often sold in convenient pouches that eliminate dust) according to the manufacturer's instructions. Insert the uplift tube over the side of the fish tank and attach to the filter box--this mechanism sucks water from the tank into the filter and through the charcoal. Hang the filter box off the outside of the tank (toward the back to hide from view) so the filtered water can pour back into the tank.

Set up the heater if you want a tropical freshwater tank (coldwater tanks do not require heaters). Most heaters are self-contained cylinders that clamp onto the top edge of the tank. Make sure the body of the heater is not touching the interior wall of the tank; it should about a half-inch from the glass.

Add the gravel, sloping from the depth of at least two inches at the front of the tank up to four or five inches at the back. Use gravel with particles one-eighth inch in diameter for the best filtering capability. Make sure the gravel does not impede any of the filter mechanisms or heater.

Place the dinner plate on top of the gravel, and pour water from a hose or bucket over the plate. Fill the tank about halfway. Remove the plate.

Choose the plants you'll include in the aquarium. Common, easy-to-grow freshwater tropical plants include Cryptocoryne, Vallisneria, Echinodorus, Sagittaria and Anubias species. Most are available at pet shops and aquarium supply stores. The number of plants you'll be able to add depends on the gallon size of your aquarium. Add enough plants to give the fish cover and places to hide, but leave room for them to swim in open water; don't overcrowd the tank.

Add the live aquatic plants. Aquatic plants are sold as cuttings tied with metal bands or rubber bands, or rooted in small pots. If buying cuttings, simply wedge the snipped ends of the plants into the gravel. If the plants are in pots, remove the pot and bury the roots into the gravel. Position the shorter plants in front and space-filling species in back. Hide the filtration system tubes or other hardware with tall plants. Attach a weight (such as a medium-sized rock) to the roots with a rubber band if the plants have a tendency to float.

Fill the remainder of the tank with water. Turn on the power source for the filtration and aeration system and heater. Place the hood on the tank and turn on the light.

Test the water quality with the water-conditioning kit; you'll be able to see results after a few minutes. Add the corrective solutions according to package directions. Adjust the pH of the water with the pH test kit if necessary. Over a period of time the solutions, plants and natural evaporation will neutralize chlorine, carbon dioxide and chemical levels.

Add fish to the aquarium only after the water-testing kit reveals neutral chemical levels.