XY 380 SPONGE FILTER

A sponge filter is a gentle, reliable form of aquarium filtration: a block of porous sponge fitted over a rigid tube, driven entirely by an air pump rather than an internal motor. Air bubbled up through the tube lifts water through the sponge, trapping debris (mechanical filtration) while the sponge's large surface area hosts a colony of beneficial bacteria that break down fish waste (biological filtration).

The XY-380 is rated for a suitable water volume of around 1050 litres, making it the largest-capacity sponge filter in this store's XY range — sized for sizeable tanks rather than nano setups. Sold as a bio-chemical sponge filter suitable for both freshwater and saltwater use, it's built for tanks that need real biological filtration capacity without the stronger, more disruptive current of a powered canister or hang-on filter.

Because sponge filters have no fast-spinning impeller and produce gentle water movement, they remain a common choice even in larger setups where fry, shrimp, or delicate fish are kept alongside the main population.

Many large-scale breeders and hobbyists running multiple tanks favour bigger sponge filters like this precisely because they offer a lot of biological media surface area per unit cost compared to canister filter media, at the price of needing a genuinely capable air pump — often a shared, larger central pump feeding several sponge filters at once rather than one small pump per tank.

A sponge filter is entirely passive by itself — it needs an air pump connected via airline tubing to actually function; without a pump pushing air through the lift tube, no water moves through the sponge. A filter rated for this much volume needs a correspondingly capable air pump to drive it effectively — an undersized pump will leave the filter underperforming relative to its rated capacity.

Being sized for larger tanks, it typically sits on the substrate, weighted or wedged in place, with clear space around the sponge for water to be drawn in freely. In a heavily stocked large tank, running more than one sponge filter (or pairing with a powered filter) is common practice for more even coverage.

If replacing or supplementing an existing filter, consider moving an already-cycled sponge or media from the old setup rather than starting biological filtration completely from zero, which avoids putting the tank through a fresh cycling period.

An adjustable flow-control valve on the airline lets you tune output without needing a smaller pump, useful in a large but lightly stocked tank where full flow isn't necessary yet.

In an especially large or oddly-shaped tank, two of these spaced at opposite ends often give more even water circulation and biological coverage than a single unit pushed to its rated limit, and it also builds in redundancy — if one filter is pulled out for cleaning, the other keeps the tank's bacterial colony running. Because of its size, some keepers also use it as the sole biological filter behind a separate mechanical pre-filter or canister, splitting mechanical and biological duties between two devices rather than asking one filter to do both jobs at this scale.

Real-world specifications and upkeep:

• Power: none directly — passive filter driven entirely by an external air pump
• Rated capacity: suitable water volume of approximately 1050 litres
• Suitable for: freshwater and saltwater tanks, biological (and mechanical) filtration for larger setups
• Cleaning: rinse gently in removed tank water (never tap water, which kills the beneficial bacteria) every 1–2 weeks; squeeze rather than scrub to preserve more of the bacterial colony
• Signs it needs attention: visibly reduced bubble flow or a dense, slimy sponge usually means it's due for a gentle rinse
• Air pump sizing: match pump output to this filter's larger rated volume, or it will underperform relative to its capacity
• Multiple tanks: a single larger air pump can often drive several sponge filters at once via a manifold/gang valve
• Flow adjustment: a flow-control valve lets you tune output down for a lightly stocked large tank
• Seeding: moving already-cycled media from an old filter helps a new setup skip a fresh cycling period
• Longevity: the sponge has no fixed lifespan and can be reused for years with regular gentle rinsing
• Positioning: leave clear space on all sides so water can be drawn in from the full surface area, not just one face
• Large/breeder setups: at this rated volume, it's a common choice as dedicated biological filtration in racked breeding systems or oversized display tanks, often paired with a separate mechanical pre-filter
• Redundancy in big tanks: running two units at opposite ends of an especially large tank spreads coverage and means the colony survives even while one is out being rinsed