Filtration

Aquarium filtration is essential for creating a healthy, stable environment by removing toxic fish waste, uneaten food, plant detritus, and debris. It acts like a liver/kidney system, utilizing biological, chemical, and mechanical processes to convert toxins into harmless compounds and plant nutrients, maintain clear water, provide water flow which evenly distributes water temperature, and promotes even gas exchange, allowing for proper aeration necessary for aquatic life.

Purpose for filtration

  • The filter takes in water and returns it to the tank with less toxins and suspended particles
  • The filter works by mechanical, biological, and chemical filtration
    • Mechanical filtration removes matter like detritus, dead plant matter, fish waste, etc., makes water look clean and clear
    • Biological filtration converts ammonia and nitrites into nitrates, performed by beneficial bacteria (nitrogen cycle) thus protecting livestock and providing nutrients for plants
    • Chemical filtration can be as simple as running water through activated carbon to remove toxins

The importance of filter turnover rate

  • Turnover refers to water flow or movement, ensuring even temperature and aeration distribution, preventing dead zones
  • Turnover is important for circulation to carry nutrients and injected CO2 throughout the tank
  • Turnover determines how often water is filtered for removing physical debris and neutralizing harmful bio-chemical compounds
  • Turnover, good water flow helps prevent algae
  • Filtration should turnover the aquarium's water volume 10x per hour
    • Manufacturers usually rate a filter's turnover capacity with gallons or liters per hour (GPH or LPH)
    • That usually means without any filter media that slows down the turnover rate
    • It's better to have more rather than less turnover

Types of filters

  • Hang on back/side filters are usually best for nano tanks
    • Filter media can be customized with filter floss, sponge, bio rings, active carbon, crushed coral, etc.
    • Filter floss and sponge trap suspended particles
    • Bio rings (Biomax) are porous ceramic which creates effective housing for beneficial bacteria
    • Activated carbon
      • Effective at removing ammonia, tannins, and other dissolved chemicals and organic compounds from the water column
      • By removing odor causing molecules it keeps water smelling fresh
      • Also helps water clarity and helps maintain stable water conditions for a healthy aquarium ecosystem
    • Crushed coral can be added to the filter media in order to increase KH and PH gently
  • External canister filters are usually best for larger tanks, having all the media customization options of hang on back filters, and more
  • In tank box filters and sponge filters are sometimes used for certain applications
  • Under gravel filters are rarely used except for special applications

Filter cleaning regularly is essential

  • Turn filter off before servicing
  • Rinse sponges and floss/fiber, bio rings, and other media
    • Always reserve the water removed during water change for this purpose to preserve the bacteria colony and nitrogen cycle
    • Never use tap water which contains chlorine which kills beneficial bacteria, causing the nitrogen cycle to restart by necessity
  • Replace bio rings, carbon, crushed coral, etc, but replace only half per filter cleaning to maintain bacteria colony
  • Use a brush on the impeller to keep clean and algae free to keep flow strong
  • The filter box should be rinsed, but not cleaned spotless in order to preserve the beneficial bacteria buildup

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