Perform Water Changes

• 1). Turn off your pump and filter.
  
  
• 2). Vacuum your gravel with an aquarium gravel vacuum. Empty the dirty water into a bucket to discard, or directly into a sink or down a drain. This removes nitrites and nitrates from your water, as well as organic waste and debris before it can be broken down into nitrites.
  
  
• 3). Remove 2 1/2 gallons of water from your 10 gallon tank while vacuuming the gravel.
  
  
• 4). Replace the 2 1/2 gallons of water you have removed from your aquarium with dechlorinated fresh water for a freshwater tank or saltwater for a marine tank.
  
  
• 5). Repeat this process twice a month or every other week.
  
  

Other Ways to Lower Nitrites

• 1). Add plants (freshwater) or live macroalgae (marine) to your aquarium. Plants and microalgae feed on nitrites and nitrates.
  
  
• 2). Add a chemical detoxifier to aquariums that removes nitrites. Follow manufacturer's instructions on the packaging.
  
  
• 3). Keep filters and skimmers clean and running smoothly.