Fluval C-Series Hang-On-Back Power Filter | up to 265L (4 ft) | Fish Bazaar
The Fluval C-Series hang-on-back aquarium filter is a 5-stage clip-on HOB power filter for fish tanks up to 265 litres (around 70 US gallons, roughly 4 feet), delivering approximat ely 1,000 litres per hour of clean, clear water. Uniquely among hang-on filters, the C-Series performs five stages of filtration — including a re-filtration step — for both freshwater and saltwater aquariums. It clips onto the back of your tank, is easy to maintain, and is one of the most capable hang-on-back filters available in India. What is the Fluval C-Series Filter? Short answer: A 5-stage hang-on-back (HOB) power filter for tanks up to 265 litres, suitable for freshwater and saltwater. In detail: The Fluval C-Series clips onto the tank rim and cascades filtered water back in. What sets it apart is its 5-stage filtration: two mechanical stages (foam pads), a chemical stage (activated carbon), and two biological stages including a unique trickle-down bio-screen that exposes bacteria to oxygen-rich air for extra efficiency. It has adjustable flow and a clog-warning indicator. For example: on a 3–4 foot community or marine tank (around 150–265 L), the C-Series keeps water polished and stable with more filtration stages than a typical HOB. Key Features 5-stage filtration — mechanical, chemical and biological, including a trickle-down bio-screen for extra oxygenated bacterial action. ~1,000 LPH flow — strong circulation for tanks up to 265 L. Freshwater and saltwater ready — versatile across tank types. Adjustable flow with re-filtration — excess water is re-filtered rather than wasted. Clog-warning indicator — tells you when maintenance is due. Easy clip-on design — simple to install and service. Benefits Immediate: Clear water and strong circulation from day one, with more filtration stages than an ordinary HOB. Short-term: The dual biological stages mature into a powerful bacterial colony, keeping ammonia and nitrite at zero. Long-term: Reliable, versatile filtration for freshwater or marine tanks, for years, with only inexpensive media to replace. How It Works The C-Series runs water through five stages — two mechanical foam pads trap fine and coarse debris, activated carbon handles chemical polishing, and two biological stages (a submerged bio-media and an oxygen-rich trickle-down bio-screen) grow the bacteria that convert toxic ammonia to nitrite and nitrate. See how aquarium filters work. Which Tank Size Is the Fluval C-Series For? Short answer: Tanks up to 265 litres — roughly up to a 4 foot aquarium. Tank length Approx. volume C-Series suitability 2–3 ft 60–120 L Good (turn flow down) 3–4 ft 120–200 L Ideal 4 ft up to 265 L Excellent 4 ft+ 265 L+ Step up to a canister or the Tidal 75/110 Suitable For Freshwater community tanks Marine and reef tanks (as supplementary filtration) Keepers who want more filtration stages from a hang-on filter Not Suitable For Tanks over 265 L — choose a canister or a larger Tidal HOB Nano and betta tanks — the flow may be strong; a small internal or sponge filter is gentler Rimless tanks where a HOB cannot clip on securely Setup & Usage Clip the filter onto the back rim, load the foam pads, carbon and bio-media, prime it, and switch on. Set the flow to suit your fish. Rinse the mechanical pads in old tank water when the clog indicator shows. Allow 4–6 weeks to cycle. See the installation guide. Technical Specifications Specification Detail Model Fluval C-Series Power Filter Filter type Hang-on-back (HOB), 5-stage Suitable tank size up to 265 L (70 US gal) Flow rate ~1,000 LPH Water type Freshwater & saltwater Maintenance alert Clog-warning indicator Best for Community & marine tanks up to 4 ft Common Problems It Solves Limited filtration of basic HOBs: five stages including a re-filtration step do more. Knowing when to clean: the clog-warning indicator tells you. Marine filtration needs: works on saltwater as well as freshwater. Cloudy water: dual mechanical plus carbon keeps it clear. Fluval C-Series vs Other Filters Feature Fluval C-Series Basic HOB Seachem Tidal Filtration stages 5 2–3 3 (large basket) Flow rate ~1,000 LPH variable 1,000–2,000 LPH Maintenance alert Yes No Yes Best tank size up to 265 L up to ~120 L up to 425 L Expert Recommendation For a community or marine tank up to 4 feet where you want more filtration from a hang-on unit, the Fluval C-Series is our top multi-stage HOB pick. Boost its biological capacity with a little Seachem Matrix or TCWS Bio-Media, and add Purigen for extra clarity. Frequently Asked Questions What tank size is the Fluval C-Series suitable for? Tanks up to 265 litres (about 70 US gallons), roughly up to a 4 foot aquarium. What is the flow rate of the Fluval C-Series? Approximately 1,000 litres per hour, with adjustable flow and a re-filtration feature. What does 5-stage filtration mean? The C-Series uses two mechanical stages, one chemical (carbon) stage and two biological stages, including an oxygen-rich trickle-down bio-screen. Can the Fluval C-Series be used on a marine tank? Yes — it works on both freshwater and saltwater aquariums. Does the Fluval C-Series tell me when to clean it? Yes — a clog-warning indicator shows when the mechanical media needs rinsing. Fluval C-Series vs Seachem Tidal — which is better? The C-Series offers five filtration stages; the Tidal offers a larger single media basket and surface skimmer. Choose by tank size and preference. How often do I clean the Fluval C-Series? Rinse the mechanical pads in old tank water when the clog indicator shows, typically every 2–4 weeks. Is the Fluval C-Series good for planted tanks? Yes — it suits planted community tanks; turn the flow down if your plants prefer gentler current. Does the Fluval C-Series come with media? Yes, it ships with foam pads, carbon and bio-media; you can add extra bio-media for capacity. Is the Fluval C-Series quiet? Yes — it runs quietly when primed and the water level is correct. Can I use the Fluval C-Series on a betta tank? On a larger betta tank, yes — turn the flow down or baffle the outflow for gentle current. Is the Fluval C-Series worth it in India? Yes — its 5-stage filtration and versatility make it excellent value among hang-on-back filters. Does the Fluval C-Series need an air pump? Usually not — the cascade and trickle bio-screen aerate well; add an air pump in hot summers for extra oxygen. Related Products & Guides Related filters: Seachem Tidal 55 / 75 (large HOBs), Fluval 307 canister. Recommended media: Seachem Matrix, TCWS Bio-Media, Purigen. Collections: Fluval Filters, Aquarium Filters. Guides: Canister vs HOB vs Sponge, Types of Aquarium Filters. Conclusion The Fluval C-Series hang-on-back aquarium filter brings 5-stage filtration — including a unique trickle-down bio-screen — to tanks up to 265 litres (4 ft) in both freshwater and saltwater. With ~1,000 LPH flow, a clog-warning indicator and easy clip-on installation, it is one of the most capable hang-on-back filters in India.