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Nutrafin Cycle Biological Filter Supplement

4.3 out of 5 stars 101 ratings

Price: $15.98 FREE Shipping
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Ships from and sold by Amazon.com.
8.4-Ounce
Standard Packaging
  • Fast-acting responsive ammonia and nitrite elimination
  • Consistent performance from each container due to bio-floc technology for improved shelf life and product viability
  • Ensures that biological pollutants produced by fish are rapidly converted to a non-harmful compound
  • Helps prevent fish loss
  • Suitable for freshwater and saltwater aquariums

Frequently bought together

  • Nutrafin Cycle Biological Filter Supplement
  • +
  • Nutrafin Waste Control Bio Aqua Cleaner
Total price: $30.97
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Product description

Size:8.4-Ounce  |  Product Packaging:Standard Packaging

Nutrafin Cycle
Nutrafin Cycle Biological Aquarium Supplement features a high-concentration formula that immediately establishes a safe biological aquarium environment. Cycle goes to work fast, releasing massive amounts of beneficial bacteria that eliminate toxic ammonia and nitrites and creates a biologically well-balanced aquarium for healthy fish to thrive. It is also ideal for quickly establishing safe and essential conditions in new aquarium setups, so that you can introduce fish to new aquariums immediately. Regular application of Nutrafin Cycle helps to competitively exclude the establishment of undesirable bacteria in aquariums.

Nutrafin Cycle is an all-natural product that will not harm plants, animals or humans. It does not require refrigeration and it can be used in fresh and saltwater aquariums. Cycle provides consistent results thanks to the unique and proprietary bio-floc technology that preserves product stability, efficacy and shelf life. High-quality production processes ensure that every container of Cycle contains pure, safe bacterial colonies free of undesirable contaminants.

When to Use Nutrafin Cycle

1. When starting any new aquarium.
2. When adding new fish.
3. When cleaning or replacing media inserts.
4. After medicating.
5. In case of fish loss.
6. As a weekly supplement to maintain optimum water quality.

What else is there to know about Cycle?

Fish keeping, like life, is all about balance. Fish will only thrive when their water is in perfect harmony, with enough good bacteria available to neutralize harmful ammonia and nitrite. Nutrafin Cycle works to keep balance your aquarium water so your fish have the ideal environment to live in.

Technical Information

Nutrafin Cycle significantly increases the speed at which robust beneficial bacteria populate the aquarium and is also able to immediately metabolize greater quantities of ammonia and nitrite. The Cycle formulation has been supercharged and adapts and responds to demanding conditions. Cycle is composed of 5 strains of nitrifying bacteria. In addition to this, heterotrophic bacteria are also included to complement the actions of the included nitrifyers by converting organic waste to inorganic (ammonia & nitrite) compounds for conversion to nitrate.

Lab testing has clearly demonstrated Cycle to be able to metabolize up to 40mg per liter of ammonia in approximately 24 hours. Nutrafin Cycle features a robust group of bacteria that are highly adaptive and responsive.

Product Benefits

Introduce Fish Immediately*

Nothing is more frustrating than staring at an empty aquarium, waiting for it to complete a fishless cycling process. With Nutrafin Cycle you can now enjoy your new aquatic world straight away as the fast acting formula immediately creates a habitable environment for your fish.

*Nutrafin Cycle will allow immediate stocking of fish when all necessary conditions have been provided, including correct temperature, proper filtration and the application of Nutrafin Aqua Plus. Fish should be introduced gradually over several weeks.

Reduce Fish Loss

Cycle's fast-acting formula gets to work immediately to quickly reduce harmful ammonia and nitrite. This means you're far less likely to lose fish in a crisis.

Easy-Measure Cap
Nutrafin Cycle


Cycle comes with an easy-measure dosage cap marked in 5ml increments, so whatever size your aquarium you can be confident the dosage is correct.

Nutrafin Cycle has been developed using the latest advances in bio-technology and has achieved improved bacterial stability, higher activity levels and an ultra-pure concentrated product for unparalleled consistent performance from every bottle.

Whether you're a new or experienced fish keeper, new Nutrafin Cycle is essential to ensure a safe, balanced home for your fish.

Dosage Information
Nutrafin Cycle


*New Aquariums:
  • Day 1: 25 mL per 10 gallons
  • Day 2: 10 mL per 10 gallons
  • Day 3: 10 mL per 10 gallons

    *All regular maintenance activities (water changes, filter maintenance, etc.):
  • 5 mL 10 gallons

    *After adding new fish and/or medicating:
  • 10 mL per 10 gallons

    *Weekly dosage to maintain a strong beneficial biological colony:
  • 5 mL per 10 gallons

  • Product details

    Size: 8.4-Ounce | Product Packaging: Standard Packaging
    • Product Dimensions: 2.3 x 2.3 x 8 inches ; 9.6 ounces
    • Shipping Weight: 9.9 ounces (View shipping rates and policies)
    • ASIN: B0026C8YJO
    • Item model number: A7902A1
    • Customer Reviews: 4.1 out of 5 stars 99 customer reviews
    • Amazon Best Sellers Rank: #120,318 in Pet Supplies (See Top 100 in Pet Supplies)
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    Customer Questions & Answers

    99 customer reviews

    March 9, 2014
    Size: 8.4-OuncePackage Type: Standard PackagingVerified Purchase
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    December 16, 2012
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    January 12, 2016
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    January 6, 2013
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    April 15, 2013
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    May 2, 2013
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    March 1, 2013
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