# Filter Cartridge Fluval U3 Clearmax replacement media FV-4821

**URL:** https://aio.lv/en/product--fluval-fv-4821--12070199
**Data updated:** 2026-03-12 21:49 (EET)
**Category:** Aquarium Supplies
**Manufacturer:** Fluval
**Manufacturer code:** FV-4821
**EAN:** 015561104821
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 11.99 €
**Prices and availability valid until:** 2026-07-17 23:59
**Price without VAT (21%):** 9.91 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--fluval-fv-4821--12070199

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 08.07.2026 | free |
| Pickup points | 13.07.2026 | 1.99 EUR |
| Courier delivery to door | 13.07.2026 | 4.99 EUR |

## Summary description

Replacement filter cartridge designed for Fluval U3 internal aquarium filters. Model FV-4821 (Clearmax) provides the factory-compatible filtration media pack for mechanical and chemical filtration in freshwater and marine tanks. Intended to trap debris and reduce impurities, it fits into compatible Fluval U3 filter units for routine maintenance and improved water clarity.

## Long description

The Fluval U3 Clearmax replacement media cartridge FV-4821 is a factory-compatible filter refill designed for Fluval U3 internal aquarium filters. It combines mechanical and chemical filtration media to trap suspended debris and reduce dissolved impurities, supporting clearer water in both freshwater and marine tanks. The cartridge is shaped to fit the Fluval U3 filter housing and is intended for routine maintenance and easy media replacement.
Advantages
This replacement cartridge offers combined mechanical and chemical filtration in a single pack, simplifying upkeep of the Fluval U3 internal filter. The mechanical layer captures particles and detritus to help prevent clogging of downstream media, while the chemical media adsorbs organic compounds and reduces discoloration. The unit is designed for straightforward replacement, ensuring consistent filtration performance and maintaining water clarity without complex installation.
Suitable for
Owners of Fluval U3 internal aquarium filters seeking original-fit replacement media
Freshwater aquariums requiring routine particle removal and impurity control
Marine tanks where chemical filtration helps reduce organics and coloration
Regular maintenance cycles to restore filter efficiency and water clarity
Key specifications
Combined mechanical and chemical filtration media
Designed to fit the internal filter cartridge compartment of compatible Fluval U3 units
Pre-formed cartridge shape for straightforward insertion and removal
Single-use replaceable media pack intended for periodic replacement during maintenance
Suitable for both freshwater and marine aquarium environments
How to use
Turn off and unplug the Fluval U3 filter before servicing. Open the filter housing according to the filter manual and remove the spent cartridge. Insert the new Clearmax replacement cartridge into the cartridge compartment, ensuring it seats correctly and aligns with the housing. Reassemble the filter housing, refill as needed, and restart the unit. Follow a regular replacement schedule based on tank bioload, manufacturer guidance, and observed water clarity.
Usage recommendations
Replace the cartridge at regular intervals or sooner if flow decreases significantly or water clarity declines. Rinse any loose debris from the filter housing during cartridge changes and monitor water parameters after installation. For optimal results, combine with routine mechanical cleaning of the filter and periodic water testing to maintain a healthy aquarium environment.

## FAQ

### How much does the Fluval U3 Clearmax filter cartridge FV-4821 cost, and is it available for purchase?

The price is 11.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 11 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 08.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All Fluval products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized Fluval service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

https://aio.lv/img/cache/product/12070199/67555132_large.webp