Fluval U4 Filter Media – Poly-Clearmax Cartridge – 2-pack
The Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite, and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance and is ideal for both freshwater and marine environments. Designed for Fluval U2 Underwater Filter, this 2-pack includes two cartridges.
Key Features
- Controls green water and algae growth by trapping phosphate, nitrite, and nitrate
- Produces crystal clear water and reduces odors
- Reduces overall aquarium maintenance
- Designed for Fluval U2 Underwater Filter
- Includes 2 cartridges
| Specification | Details |
|---|---|
| Product Type | Filter Media Cartridge |
| Quantity | 2 Pack |
| Compatible Filter | Fluval U2 Underwater Filter |
| Environment | Freshwater and Marine |
FAQ
Can this cartridge be used in both freshwater and marine aquariums?
Yes, the Fluval Poly-Clearmax cartridge is designed for use in both freshwater and marine environments.
Does this cartridge remove all algae from the aquarium?
The cartridge helps reduce algae growth by trapping phosphate, nitrite, and nitrate, but it does not eliminate all algae. Regular maintenance and proper water changes are still recommended.
Is this product compatible with Fluval U4 filters?
Please contact customer service. This product is designed for Fluval U2 Underwater Filter, not U4.

James Stewart –
I’ve used this cartridge for three months now and noticed a significant reduction in green water and algae. My tank looks much clearer and the fish seem more active. Easy to install and fits perfectly with my Fluval U2 filter.
Felicity Mitchell –
The water clarity improved noticeably after switching to the Poly-Clearmax cartridges. I still do weekly water changes, but I find myself doing them less often. The smell in the tank has also decreased.
Abigail Nash –
Great product for controlling phosphate levels. After using the two cartridges, my aquarium has stayed clean without needing frequent cleaning. Works well in a mixed freshwater and plant setup.
Owen Langdon –
It helps with water clarity, but I noticed the filter needs to be replaced every few months. The performance is steady, but not as strong as some other media I’ve tried.