Best Filtration Systems for 100–200L Tanks (2026)

The 100 to 200-litre aquarium is the sweet spot for many hobbyists, offering enough space for a vibrant community without the demands of a massive tank. The heart of any successful aquarium is its filtration system. A good filter keeps the water clean, clear, and, most importantly, healthy for your fish. This guide compares the best types of filters for mid-sized tanks available in South Africa.

Canister vs Hang-on vs Sponge

Canister Filters

Pros: Huge media capacity, excellent mechanical and biological filtration, quiet operation, and keeps equipment outside the tank.
Cons: More expensive, can be complex to set up and clean.
Best for: Heavily stocked tanks, planted tanks, or anyone wanting maximum filtration power.

Hang-on-Back (HOB) Filters

Pros: Easy to install and maintain, affordable, provides good surface agitation.
Cons: Less media capacity than canisters, can be noisy.
Best for: Most standard community tanks with a moderate bioload.

Sponge Filters

Pros: Very cheap, gentle flow (safe for fry and shrimp), excellent biological filtration.
Cons: Provides little mechanical filtration, can be an eyesore.
Best for: Breeding tanks, shrimp tanks, or as a supplementary biological filter.

Matching Flow to Bioload

A filter's flow rate, measured in Litres Per Hour (LPH), is crucial. A good rule of thumb is to have a filter that turns over the total volume of your tank 4-6 times per hour. For a 150L tank, you'd want a filter with a flow rate of at least 600-900 LPH. For heavily stocked tanks (like African Cichlids), aim for 8-10 times turnover.

Maintenance Checklist

Never clean your filter media with tap water, as the chlorine will kill your beneficial bacteria. Instead, rinse sponges and ceramic media in the old tank water you remove during a water change. Replace filter floss or polishing pads monthly. Don't replace all your media at once; do it in stages over several weeks to preserve your biological filter.