Fluval AC30 Power Filter 10-30 US Gal / 38-114 L

Fluval's AquaClear-based hang-on-back power filter, delivering 4-stage filtration (mechanical, chemical, and biological, plus the brand's CycleGuard bio-support) in a single unit rated for tanks up to 30 US gallons. The large media basket holds substantially more filter media than most HOB filters in its class, which means longer intervals between maintenance and more stable biological filtration during water changes or media swaps, since you're never replacing all the media at once.