Shark PRO 900 Internal Filter (238 GPH) - Sicce

The Shark PRO 900 is Sicce's redesigned take on the internal filter — a category that often trades convenience for performance. At 238 GPH and 10 watts, it delivers meaningful flow for tanks up to 70 gallons without the noise or footprint of a hang-on-back unit. The modular cartridge architecture is the defining feature: each cartridge snaps onto the filter head magnetically, so cleaning is a matter of pulling the module free rather than disassembling the whole unit. Critically, cartridges can be removed while the pump continues running, which avoids the nutrient spike that comes from halting flow during maintenance.

The expansion system gives the Shark PRO 900 real longevity. The unit ships with three cartridge modules and accommodates up to two additional ones, letting you layer mechanical and biological media as your bioload increases. This modular approach also makes media swaps straightforward — replace one cartridge at a time to preserve established bacterial colonies rather than disrupting the whole filter bed at once.

Mounting flexibility is a practical asset. The filter attaches to glass up to 12mm thick via a magnetic bracket and can be oriented vertically or horizontally, which is useful in shallow tanks or unconventional setups. The integrated spray bar distributes oxygenated return flow across the water surface, reducing the need for a separate airstone. Assembly is tool-free, and Sicce rates operation as silent — a reasonable claim for a unit drawing only 10 watts.

The Shark PRO 900 is best suited to lightly to moderately stocked freshwater aquariums. The 70-gallon rating assumes that stocking level; heavily loaded systems or marine tanks should look to external filtration. The included foam media gets you running immediately, though the modular slots make it easy to add ceramic biomedia or specialty cartridges as the tank matures. Made in Italy with a five-year guarantee, it's a well-considered option for hobbyists who want internal filtration that doesn't punish them at water change time.