--- product_id: 13829343 title: "CNZ Aquarium Bio Cylinder Nano Sponge Filter 2\" x 4.75\", Set of 6" brand: "cnz" price: "€ 49.81" currency: EUR in_stock: true reviews_count: 8 category: "Cnz" url: https://www.desertcart.hr/products/13829343-cnz-aquarium-bio-cylinder-nano-sponge-filter-2-x-4 store_origin: HR region: Croatia --- # Dual mechanical & bio filtration 2" x 4.75" compact size Reusable & easy maintenance CNZ Aquarium Bio Cylinder Nano Sponge Filter 2" x 4.75", Set of 6 **Brand:** cnz **Price:** € 49.81 **Availability:** βœ… In Stock ## Summary > 🧽 Elevate your nano tank game with effortless, pro-grade filtration! ## Quick Answers - **What is this?** CNZ Aquarium Bio Cylinder Nano Sponge Filter 2" x 4.75", Set of 6 by cnz - **How much does it cost?** € 49.81 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/13829343-cnz-aquarium-bio-cylinder-nano-sponge-filter-2-x-4) ## Best For - cnz enthusiasts ## Why This Product - Trusted cnz brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Fish-Safe Flow:** Gentle current ideal for delicate fry and small species, preventing accidental suction injuries. - β€’ **Dual-Action Filtration:** Combines mechanical debris removal with powerful biological waste breakdown for crystal-clear water. - β€’ **Nano-Perfect Dimensions:** Compact 2" x 4.75" size fits seamlessly in nano and quarantine tanks. - β€’ **Universal Compatibility:** Optimized for both freshwater and saltwater environments, making it versatile for any setup. - β€’ **Low-Maintenance Longevity:** Easy to clean and reusable sponge design with recommended replacement every 3-6 months for peak performance. ## Overview The CNZ Aquarium Bio Cylinder Nano Sponge Filter is a compact, dual mechanical and biological filtration system designed for nano, quarantine, and breeding tanks. Measuring 2" x 4.75", this set of 6 sponges ensures gentle water flow safe for fry and small fish, while efficiently breaking down harmful waste in both freshwater and saltwater environments. Easy to install and maintain, it offers a low-energy, reusable solution that keeps your aquatic ecosystem thriving with minimal effort. ## Description How Does It Work? A sponge filter uses bubbles of air from an external air pump, or an integral water pump to draw water through the sponge. As water is drawn out through the lift tube or pump, it is replaced by water entering the sponge. The sponge is a mechanical filter and the surface of all the bubbles or pockets in the sponge provide a bed for the biological filter. The Bio- help to break down harmful waste (ammonia and nitrite). Sponge filters provide both mechanical and biological filtration. Most sponge filters are reasonably efficient filters for small volume tanks. These filter are excellent for small size fish like dwarf cichlid, guppy, killifish etc., or for hatcheries, maternity tanks, and fry tanks, as the filter produces minimal current and has almost no way to suck the fish through the filter. Also, the air infusion chamber produces minute bubbles which increase the oxygen solubility. What Maintenance Does It Require? The sponge will need to be rinsed every time it becomes dirty, about once every 2 to 4 weeks. It’s helpful to reserve the Bio-filtration by washing the sponge gently with water from the fish tank instead of tap water. After 3 to 6 months’ usage, the micro holes of sponge is gradually clogged by the tiny debris, the bio-filtration won’t have as much living space as before. That’s when the sponge filter starts to lose its efficiency. So it is also recommended to replace the sponge once every three to six month or when the sponge gets worn out. Review: great little sponge filter - Working great so far in my 2.5 gallon betta tanks Review: Great for small breeder tanks - Great small filters for my 10 gallon breeder rack. Paired with a 4 outlet air pump makes a great low energy filter solution that won't injure fish fry. ## Features - This foam filter is designed to be easy to install, easy to maintain and easy to clean. - Dimension: 2.0" x 4.75(h) with tube each, Ideal for nano tanks, quarantine tanks, fry-holding or breeding tanks. - Helps to break down organic waste and offers your tank biological filtration. - Optimized for both freshwater and saltwater tanks. - Package content : 6 x sponge water filter(small) ## Technical Specifications | Specification | Value | |---------------|-------| | Customer Reviews | 4.5 out of 5 stars 50 Reviews | ## Images ![CNZ Aquarium Bio Cylinder Nano Sponge Filter 2" x 4.75", Set of 6 - Image 1](https://m.media-amazon.com/images/I/71wrfFUvDfS.jpg) ![CNZ Aquarium Bio Cylinder Nano Sponge Filter 2" x 4.75", Set of 6 - Image 2](https://m.media-amazon.com/images/I/51iSosdcqrL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ great little sponge filter *by A***R on February 1, 2018* Working great so far in my 2.5 gallon betta tanks ### ⭐⭐⭐⭐⭐ Great for small breeder tanks *by J***J on October 20, 2018* Great small filters for my 10 gallon breeder rack. Paired with a 4 outlet air pump makes a great low energy filter solution that won't injure fish fry. ### ⭐⭐ They are not nano *by R***B on March 31, 2024* They are big. Should have advertised as small not nano. ## Frequently Bought Together - Aquarium Bio Cylinder Nano Sponge Filter 2" x 4.75", Set of 6 - Penn-Plax Standard Airline Tubing for Aquariums – Clear and Flexible – Resists Kinking – Safe for Freshwater and Saltwater Fish Tanks – 25 Feet --- ## 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.hr/products/13829343-cnz-aquarium-bio-cylinder-nano-sponge-filter-2-x-4](https://www.desertcart.hr/products/13829343-cnz-aquarium-bio-cylinder-nano-sponge-filter-2-x-4) --- *Product available on Desertcart Croatia* *Store origin: HR* *Last updated: 2026-09-03*