HW‑603 – external pre-filter

This 2.5 l prefilter is intended for aquarists who run an external canister filter and want to reduce how often the main filter needs to be opened and cleaned. It sits on the intake line and catches mechanical debris before the water reaches the filter media, which keeps the main unit working at its intended flow for longer.

Why it matters

• All mechanical contamination is collected in the prefilter, so the main filter receives cleaner water and its media stays cleaner.
• Its large capacity extends the interval between servicing the main filter, which reduces the time spent on routine maintenance.
• The housing is moulded from ABS, a dense and impact-resistant plastic, and is sealed with rubber gaskets for a stable, leak-resistant build.
• Four lever-and-latch clamps press the lid down firmly. Valves on the hose connections can be closed and detached together with the hoses, so the prefilter can be serviced without draining the system.

Specifications

• Capacity: 2.5 l
• Flow rate: 250 to 2500 l/h
• Hose connection: 16/22 mm or 16/20 mm
• Dimensions: 165 x 165 x 295 mm
• Weight: 1.35 kg
• Housing material: ABS
• Gaskets: rubber

What it works with

The prefilter is designed for any external filter operating within the 250 to 2500 l/h range, so the flow rate of the main filter determines compatibility. It suits freshwater and marine aquariums where the external filter handles mechanical load, and it is especially useful with heavily stocked tanks or systems that produce a lot of debris.