External & Canister Aquarium Filters

External Aquarium Filter Buying Guide

An external filter draws water from the aquarium, passes it through filter media and returns it to the tank. Canister filters sit below or beside the aquarium, while hang-on-back filters mount on the rim; the right format depends on the tank, cabinet space, livestock and maintenance preference.

• Check the rated aquarium volume, but also allow for fish load and waste production.
• Confirm the filter will physically fit the cabinet or tank rim, including hose and service clearance.
• Compare usable media space, supplied media, priming method, flow control and replacement-part availability.
• Choose gentle or adjustable return flow where livestock may be stressed by strong current.

Choosing an External Filter

Canister Filters

Canister filters provide enclosed media baskets and are useful where substantial mechanical and biological media capacity is wanted. Check hose size, head height and the manufacturer’s installation instructions.

Hang-On-Back Filters

Hang-on-back filters are accessible and avoid hoses running into a cabinet. Confirm rim clearance, water-level requirements and whether the return flow suits the aquarium.

Flow Rate and Tank Size

Published litres-per-hour figures are useful for comparison, but real flow changes with media, hose length, lift height and dirt accumulation. Use the model’s guidance and choose for the actual stocking level.

Use and Maintenance

Disconnect power before opening or servicing the filter. Clean mechanical media when debris restricts flow and inspect hoses, seals and the impeller as directed by the manufacturer.

Preserve biological stability by avoiding the simultaneous replacement or aggressive cleaning of all established biological media. After servicing, check for leaks and confirm the filter has restarted correctly.

Complete Your Setup

Pair the filter with suitable filter media, or compare internal filters and sponge filters for other layouts.

Buy External Aquarium Filters Online in Australia

Browse current external and canister aquarium filters online for Australia-wide delivery. Product availability changes, so check each listing for included media, exact dimensions, warranty information and compatibility before purchase.

Frequently Asked Questions

What is an external aquarium filter?

It is a filter whose main body sits outside the aquarium. Canister filters usually connect by inlet and return hoses, while hang-on-back filters mount on the tank rim.

Is a canister filter better than an internal filter?

Neither is universally better. Canisters generally offer more external media space, while internal filters can be simpler and more compact. Choose according to tank size, livestock, space and maintenance needs.

How do I choose the correct filter size?

Use the manufacturer’s aquarium-volume guidance, then consider stocking level, fish size, waste production, head height and desired flow. Heavily stocked tanks may need more capacity.

How often should an external filter be cleaned?

There is no universal interval. Service it when flow falls or media accumulates debris, while following the manufacturer’s directions and avoiding unnecessary disturbance of biological media.

Do external filters come with filter media?

Some models include media and others require additional or replacement media. Check the individual product listing because inclusions differ between models.