Fluval AC20/30 BioMax Insert

The Fluval AquaClear BioMax Insert is high-porosity ceramic ring media that gives beneficial bacteria a massive surface area to colonize inside your AquaClear 20 or AquaClear 30 hang-on-back filter. Those bacteria are what power your nitrogen cycle, converting toxic ammonia and nitrite into far safer nitrate. More surface area means a bigger, more stable biological filter and a healthier tank.

Building out your filter or restocking media? Browse all filter media and cartridges at Squeaky's Aquatics.

Why AquaClear BioMax

• Promotes bio activity. The complex network of pores in each ceramic ring hosts far more bacteria than smooth media, so your tank processes waste faster.
• Maintains a healthy nitrogen cycle. A strong biological bed keeps ammonia and nitrite at zero, the single most important factor in fish health.
• Long lasting and reusable. Rinse it gently in old tank water and put it back. Ceramic media lasts for months before it needs replacing.
• Freshwater and saltwater safe. The ceramic is inert and works in tropical, coldwater, and marine aquariums alike.

Where It Fits in the AquaClear System

AquaClear power filters run three stages: water passes through the BioFoam first, then activated carbon or a carbon blend, then BioMax ceramic rings for the final biological polish. BioMax sits at the top of the stack so bacteria get clean, oxygen-rich water to do their work.

How to Use

• Fits the Fluval AquaClear 20 (AC20, Mini) and AquaClear 30 (AC30) power filters. One insert covers both models.
• Rinse in dechlorinated or used tank water every few weeks. Never rinse under hot tap water, which kills the bacteria you are trying to grow.
• When it is time to replace it, swap out only half at a time so you never reset your whole biological filter at once.
• Great insurance when cycling a new tank, adding fish, or upgrading your filtration.

Specifications

Recommended Pairings

• Fluval AquaClear Power Filter, the hang-on-back filter this insert is built for.
• Pair with the AquaClear BioFoam for mechanical filtration and the Clear-Carb for chemical filtration.
• Running a larger filter? Grab the AC50 or AC70/110 BioMax instead.

Frequently Asked Questions

How often should I replace BioMax?
Ceramic media lasts a long time. Replace it every few months, and only swap out half at a time so the remaining rings keep your bacteria colony alive.

Can I rinse it in tap water?
No. Chlorine in tap water kills beneficial bacteria. Always rinse BioMax in dechlorinated water or a cup of old tank water.

Does it work in saltwater?
Yes. The ceramic is inert and safe for freshwater, brackish, and marine aquariums.

Is this the same as the old AquaClear BioMax?
Yes. Fluval BioMax is the current name for what was formerly labeled AquaClear BioMax for the same filters.