Cycle Biological Enhancer

Cycle Biological Enhancer

Item #: VA8346 | UPC: N/A


Fluval Cycle Biological Enhancer goes to work fast, releasing massive amounts of beneficial bacteria that eliminate toxic ammonia and nitrite to establish a biologically-balanced aquarium.

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  • All-natural water care – creates a safe biological habitat to prevent fish loss
  • Infused with a powerful team of beneficial bacteria that immediately inoculates aquarium water
  • Extremely effective when setting up a new aquarium or introducing new fish to an existing one
  • Equally useful during water changes and filter media changes, when good bacteria is depleted
  • Regular application helps to completely exclude establishment of undesirable bacteria
  • Eliminates ammonia and nitrite
  • Bio-Floc technology ensures product stability and efficacy, devoid of any contaminants
  • For use in freshwater and saltwater aquariums

Label Info

  • 4 fl oz / 120 ml bottle treats aquarium up to 240 US Gal / 908 L
  • 8.4 fl oz / 250 ml bottle treats aquariums up to 500 US Gal / 1892 L
  • 16.9 fl oz / 500 ml bottle treats aquarium up to 1000 US Gal / 3785 L
  • 0.5 US Gal / 2 L bottle treats aquariums up to 4000 US Gal / 15140 L

Take a Deeper Dive

Learn more about this series and find out how it can help offer a better fishkeeping experience.

Questions & Answers

How do you cycle an aquarium?
I would like to cycle a new fishless aquarium by using decomposing food or by adding ammonium chloride. Can I use Cycle Biological Enhancer with this option?

Yes, but we don’t recommend either method. Adding ammonium chloride or fish food to a new, empty aquarium usually results in excess ammonia concentrations, which prolong the cycle and add unnecessary pollution. Fluval Cycle Biological Enhancer contains organic matter for the bacteria to consume, effectively establishing a nitrogen cycle. If you already have a healthy aquarium, transfer some established filter media from it to your new tank and dose with Fluval Cycle Biological Enhancer. Remember to stock a new aquarium slowly to not overload the biological filtration.

Why should I dose my tank with Cycle Biological Enhancer regularly?

Frequent dosing of Cycle Biological Enhancer helps to maintain a safe, biologically-stable environment by adding in beneficial nitrifying bacteria. Without regular supplementation of this product, less desirable bacteria can dominate your tank and increase the risk of ammonia and nitrite spikes. Use Cycle Biological Enhancer weekly for optimal conditions, and in particular during water changes and filter media changes.

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