Fluval U4 - Internal Filter Air Diffusers low-ash and highly porous carbon

low-ash and highly porous carbon is highly effective at removing heavy metals

Prevents nuisance algae and enables control of zooxanthellae for optimum coral growth and coloration

EXPERT: After determining the alkalinity consumption rate

5 cup per 500 gallons of pond water twice a week for 2 weeks

accelerated coral growth

Fluval U4 - Internal Filter Air Diffusers low-ash and highly porous carbonFeatures Designed for aquariums up to 65 US Gal 150 L Use as a primary filter for smaller aquariums, or supplementary filter for larger aquariums Position horizontally for shallow tanks, larger tanks with low water levels, or to create a decorative waterfall feature Position vertically against aquarium wall to create currents or customized flow patterns Convenient flip top lid allows for quick and easy access to filter cartridge for maintenance or