Goldfish are easy pets requiring basic care -- until the fish tank or bowl starts smelling. Since the buildup of fish waste is what causes the unwanted stench, simple cleaning and water changes are the easiest way to clear up the offensive odor and ensure a healthy goldfish.
Step 1
Scrape any algae -- typically brown or green -- from the glass with a special algae scraper. Algae builds up as a result of too much waste in the tank or bowl from the goldfish.
Step 2
Remove 15 to 20 percent of the water in the goldfish tank with an aquarium vacuum. When suctioning, pull water from the bottom of the tank to remove additional waste hiding in the gravel. For tanks, do this once a day for several days until the smell dissipates. If your goldfish lives in a bowl, empty it completely and wash it out, placing the goldfish elsewhere for safety.
Step 3
Replace the water removed from the tank or bowl with fresh water. This can be tap water that has been allowed to sit out overnight to dissipate chlorine and other chemicals in the water, and bring the water to room temperature so that the goldfish are not stressed from a sudden water temperature change.
Step 4
Move the fish bowl or tank to an area with less sunlight. Placing the tank or bowl in sunlight allows it to combine with the goldfish waste and provides perfect conditions for algae growth.
Step 5
Add water conditioner after switching water to assist in keeping the goldfish tank or bowl clean and clear, as well as to promote good health and less stress for your goldfish.
