--- product_id: 707365901 title: "Cycle Biological Enhancer, Aquarium Water Treatment, 8.4 Oz., A8349" brand: "fluval" price: "88.37 DT" currency: TND in_stock: true category: "Fluval" url: https://www.desertcart.tn/products/707365901-cycle-biological-enhancer-aquarium-water-treatment-8-4-oz-a8349 store_origin: TN region: Tunisia --- # Eliminates toxic ammonia & nitrite Instant beneficial bacteria boost Supports biological balance in fresh & saltwater Cycle Biological Enhancer, Aquarium Water Treatment, 8.4 Oz., A8349 **Brand:** fluval **Price:** 88.37 DT **Availability:** βœ… In Stock ## Summary > 🦠 Transform your tank into a thriving aquatic paradise instantly! ## Quick Answers - **What is this?** Cycle Biological Enhancer, Aquarium Water Treatment, 8.4 Oz., A8349 by fluval - **How much does it cost?** 88.37 DT with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/707365901-cycle-biological-enhancer-aquarium-water-treatment-8-4-oz-a8349) ## Best For - fluval enthusiasts ## Why This Product - Trusted fluval brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Bacteria Barrier:** Regular use prevents the growth of harmful bacteria, ensuring a thriving habitat. - β€’ **New Tank Essential:** Perfect for new setups and during water or filter changes to maintain a healthy ecosystem. - β€’ **Toxicity Terminator:** Effectively neutralizes harmful ammonia and nitrite to protect your aquatic life. - β€’ **Universal Compatibility:** Safe and effective for both freshwater and saltwater aquariums, 8.4 oz bottle. - β€’ **Rapid Aquarium Stabilizer:** Kickstart your tank with a powerful bacterial inoculation for immediate fish introduction. ## Overview Fluval Cycle Biological Enhancer is an 8.4 oz liquid treatment that rapidly introduces beneficial bacteria to aquarium water, eliminating toxic ammonia and nitrite. Ideal for new tanks, water changes, and filter maintenance, it supports a balanced, healthy environment for freshwater and saltwater fish, preventing harmful bacteria growth and ensuring immediate fish safety. ## Description Fluval Cycle Biological Enhancer is a responsive biological aquarium supplement that ensures that all aquariums are immediately inoculated with a powerful team of beneficial bacteria, providing a safe biological habitat for your fish. These highly effective micro-organisms will create a biological flora that quickly metabolizes lethal ammonia and nitrite and allow for the immediate introduction of fish. Fluval Biological Enhancer goes to work fast, releasing massive amounts of beneficial bacteria that eliminate toxic ammonia and nitrite to establish a biologically-balanced aquarium. Fluval Biological Enhancer is strongly recommended for new aquarium set-ups and regular application will help to exclude the establishment of undesirable bacteria in aquariums. For more fish tank accessories, check out other Fluval products including aquarium filters, aquarium heaters, aquarium air pumps, aquarium lights, aquarium rocks, aquarium thermometers, and aquarium stands. Fluval has a wide variety of products that are perfect for your pet fish to enjoy in any large fish tank, small fish tank, saltwater tank or freshwater tank. Fluval broke onto the aquatic scene in 1975 by introducing the world’s first 3-stage filter with synchronous motor technology – a breakthrough that is still applied in the industry today. Since then, Fluval has built a legacy around this pioneering spirit, relentlessly adapting in a changing world to launch innovative aquarium products that remain at the forefront of technology, and which set the bar in quality, style and functionality. Fluval’s mission is not just about building products that mimic the natural world, but inspiring aquarists of all skill levels to enjoy and respect the hobby for generations to come. ## Features - All-natural water care creates a safe biological habitat to prevent fish loss by eliminating ammonia and nitrite - 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 and useful during water changes and filter media changes, when good bacteria is depleted - Regular application helps to completely exclude establishment of undesirable bacteria - 8.4-ounce bottle for use in freshwater and saltwater aquariums ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00FPIZ8Y0 | | ASIN | B00FPIZ8Y0 | | Allergen Information | Allergen-Free | | Best Sellers Rank | #21,171 in Pet Supplies ( See Top 100 in Pet Supplies ) #169 in Aquarium Water Treatments | | Brand Name | Fluval | | Customer Reviews | 4.7 4.7 out of 5 stars (2,671) | | Date First Available | October 1, 2013 | | Department | Unisex-Adult | | Global Trade Identification Number | 00015561183499 | | Included Components | All items listed in description. | | Item Form | Liquid | | Item Type Name | Aquarium Water Treatment | | Item Weight | 8.45 ounces | | Item model number | A8349 | | Liquid Volume | 8.4 fluid ounces | | Manufacturer | Rolf C. Hagen (USA) Corp. | | Manufacturer | Rolf C. Hagen (USA) Corp. | | Manufacturer Part Number | A8349 | | Model Number | A8349 | | Number of Items | 1 | | Number of Packs | 1 | | Pet Type | Amphibian, Fish, Reptile | | Product Dimensions | 2.3 x 2.3 x 6 inches; 8.45 ounces | | Target Species | Fish | | UPC | 015561183499 | | Unit Count | 1 Count | | Warranty Description | Manufacturer Warranty | ## Product Details - **Brand:** Fluval - **Item Form:** Liquid - **Item Weight:** 8.45 ounces - **Liquid Volume:** 8.4 fluid ounces - **Number of Packs:** 1 ## Images ![Cycle Biological Enhancer, Aquarium Water Treatment, 8.4 Oz., A8349 - Image 1](https://m.media-amazon.com/images/I/71CbLgtkAbL.jpg) ## Questions & Answers **Q: How much do I need for setting up a new 75g freshwater tank?** A: After tank is set up, keep everything running except for lights and if you are running a saltwater tank keep the protein skimmer off. Pour in half of 16.9 oz. bottle upon set up, On the 8th day ,pour the rest in. In my experience on day 14 your tank is cycled, however testing tank water , 1 time I had to wait 16 days. It is recommended to dose the tank when new arrivals are added, I did this for 1week then stopped, I have used this item for 15 years when the original was sold under the CYCLE name which came in 8oz. and 16 oz. Works every time. **Q: What size bottle is recommended for a 6 gallon tank?** A: The 8.4 oz seems like a better deal overall compare to the 1oz and 4 oz. its a little cheaper. However, you would need this every time you do a water change. Some people don't add more when then do a water change, but when you take out water from your tank, your taking out some of the bacteria, thats why its necessary to replace the bacteria. This is by far one of my favorite nitrifying bacteria. This is good to cycle a tank. Plus this bacteria is something you cannot overdose. So for a six gallon tank you can add three to 4 full caps to get a good amount of bacteria in there to start the cycle. Then you can add your first fish. After you add your first fish wait for a few weeks before you add more fish. The first initial fish will help feed the bacteria you put in. This way over a few weeks it will create the ecosystem you want. To be honest Allie, some people add two much fish the first time they get an aquarium and its a big mistake. Eventually they may have a lot of fish loss due to they tank not being a ecosystem. You want to make sure you create the ecosystem first before you add a lot of fishes. Thats why for the size of your tank one fish is ok with the addition of the bacteria will help create the ecosystem. After a few weeks you can add more. Also if you are doing tropical or saltwater fish make sure you have a heater. If your doing goldfish your not required to have a heater. Acclimate your fishes well too. If you have any more questions feel free to contact me. **Q: What size do I need for a 40 gallon breeder tank?** A: The directions state 25 ml per 10 gallons on day 1 (100 ml) and then 10 ml per 10 gallons on day 2 and 3 (40 ml per day) so a total of 180 ml for your 40 gallon breader. I do a sustainment treatment every week of 5 ml per 10 gallons (another 20 ml). I think this is a great way to get and keep a large colony of beneficial bacteria. Good luck with the new tank! **Q: If I put this in a new tank how quickly will it cycle the tank? Will the bacteria stay in the tank or die off after a bit? Is it cycled permanently?** A: I would recommend API Stress Zyne Plus. My fish kept dying for the first few weeks. It took almost 8 weeks to for the tank to cycle. So get 2 or 3 fist to start and nothing fancy. Keep testing for Amonia levels. Once the tank cycles, it should be at 0. Then you can get fish you want to keep. ## Frequently Bought Together - Fluval Cycle Biological Enhancer, Aquarium Water Treatment, 8.4 Oz., A8349 - Fluval Waste Control Biological Cleaner, Aquarium Water Treatment, 8.4 Oz., A8355 - Fluval Clarify Bio for Aquarium Water Treatment, 4-Ounce --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.tn/products/707365901-cycle-biological-enhancer-aquarium-water-treatment-8-4-oz-a8349](https://www.desertcart.tn/products/707365901-cycle-biological-enhancer-aquarium-water-treatment-8-4-oz-a8349) --- *Product available on Desertcart Tunisia* *Store origin: TN* *Last updated: 2026-10-18*