Aquarium Maintenance Tips

Weekly, biweekly and monthly maintenance is an important part of keeping a healthy aquarium.

Water Changes

  • Water changes are essential to a successful aquarium.
  • A water change should be performed approximately every two weeks. Usually, 10-15% is enough.
  • It is essential to check the new water you are introducing to the aquarium. Tap water can contain chlorine or chloramine, which must be eliminated before adding the water to the tank.
  • Local tap water can also contain phosphates, iron and other heavy metals. Call your local water company to find out about your tap water chemistry.


  • It is essential to check water chemistry on a regular basis. The vital parameters to test in your aquarium are pH, nitrates, nitrites, carbonate hardness and, for marine tanks, salinity.
  • pH should be at 6.5-7.5 for most species.
  • Nitrites should be zero at all times (except during cycling). If nitrites are detected make sure you check your ammonia also.
  • Nitrate should be kept below 10 ppm in freshwater and 5 ppm in marine and reef (preferably 0 ppm).

Recommended Maintenance Routine


  • Be aware of how your fish are acting. Changes in behavior can indicate a potential problem.
  • Check your equipment to ensure it is running properly.


  • Keep a current inventory of the livestock in your aquarium.
  • Dead animals can decompose very quickly, which can easily cause an ammonia and/or nitrite spike, which then leads to high nitrate levels.


  • Test your water for:
    • pH
    • Ammonia
    • Nitrite
    • Nitrate
    • Salinity (in salt and reef tanks)
  • Vacuum the gravel and change 10-20% of the water.
  • Clean the aquarium glass.
  • Rinse filter cartridges with the water you pulled from the tank.
  • Replace carbon and filter floss (if present).
  • Inspect all equipment and parts for proper operation.

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