Install pump as directed. Connect to under gravel filter. Connect air stone to pump. This will greatly enhance the oxygenation of the water and improve water quality for the fish. Well oxygenated water results in brighter colored fish.
Poor color is a sign of low oxygen in the aquarium.
The rising cascade of bubbles is a pleasant feature of an aquarium. Place thermometer on front or side window of aquarium. Install a back filter if desired. The combination of the tank filter with an under water filter will greatly lessen the need for aquarium maintenance as particulate matter will be steadily removed. Place decorative rocks or flower pots into the gravel.