How to Choose the Right Aquarium Filter Type
Learning how to choose aquarium filter type guide options correctly is one of the most important decisions for any fishkeeper. The right filter keeps your water crystal clear, supports beneficial bacteria and maintains a healthy environment for your livestock. At Gensou Aquascaping, 5 Everton Park, we stock and recommend filters suited to every type of setup in Singapore.
The Three Types of Filtration
Every aquarium filter performs three functions in varying degrees. Mechanical filtration physically removes debris and particles from the water using sponges, filter floss or pads. Biological filtration provides surface area for beneficial bacteria to convert toxic ammonia into harmless nitrate. Chemical filtration uses media like activated carbon or Purigen to absorb dissolved pollutants, discolouration and odours. The best filters excel at all three.
Hang-On-Back Filters
Hang-on-back filters, or HOB filters, clip onto the rim of your tank and draw water up through a siphon tube, pass it through filter media, and return it via a waterfall-style spillway. They are affordable, easy to maintain and well-suited to tanks up to 100 litres. Popular models include the AquaClear series and Seachem Tidal range, priced between SGD 20 and SGD 70 in Singapore.
The main drawback is limited media capacity compared to canister filters. HOB filters also create surface agitation, which is beneficial for gas exchange but can reduce CO2 efficiency in high-tech planted tanks. They are visible on the back of the tank, which some aquascapers find aesthetically displeasing.
Canister Filters
Canister filters sit externally, usually inside the cabinet below the tank, and connect via inlet and outlet hoses. They offer the largest media capacity, the strongest flow rates and the most versatile media configuration of any filter type. Brands like Eheim, Fluval, Oase and SunSun are widely available in Singapore, with prices ranging from SGD 60 for budget models to SGD 350 for premium units.
Canister filters are the top choice for planted tanks and medium to large aquariums. Their sealed design allows pressurised flow through multiple media baskets, and the inlet and outlet pipes can be positioned for optimal water circulation. The downside is higher cost, more complex maintenance and the need for priming after cleaning.
Sponge Filters
Sponge filters are the simplest and cheapest option, consisting of a sponge attached to an air-driven uplift tube. They provide excellent biological filtration and gentle flow, making them ideal for breeding tanks, shrimp tanks and fry grow-out containers. A sponge filter costs as little as SGD 3 to SGD 10, plus SGD 15 to SGD 30 for an air pump to power it.
The disadvantage is minimal mechanical filtration and no chemical filtration. Sponge filters also take up visible space inside the tank. However, for Caridina shrimp keepers in Singapore, sponge filters are considered the gold standard due to their gentle flow and inability to trap shrimplets.
Internal Filters
Internal power filters mount inside the tank using suction cups and combine a small pump with a sponge or cartridge. They suit tanks up to 60 litres and are popular in nano setups. Brands like Eheim and Dennerle make compact internal filters priced at SGD 15 to SGD 50. Their main limitations are small media capacity and the fact that they occupy space inside the tank, reducing the available area for aquascaping.
Sump Filters
Sumps are separate tanks, usually housed in the cabinet below the display tank, that receive water via an overflow and return it with a pump. They offer virtually unlimited media capacity, house equipment like heaters and reactors out of sight, and increase total water volume. Sumps are standard in marine setups and increasingly popular for large freshwater tanks.
The cost is significant, with a complete sump setup running SGD 200 to SGD 800 or more depending on size and accessories. Installation requires drilling the tank or using a hang-on overflow box, and the system needs careful balancing to prevent flooding during power outages.
Matching Filter to Tank Type
For nano tanks under 30 litres, a sponge filter or small internal filter is sufficient. For community tanks from 30 to 100 litres, a hang-on-back filter offers the best balance of performance and convenience. Planted tanks and setups from 100 to 400 litres benefit most from a canister filter. Large tanks above 400 litres or marine setups warrant a sump system.
Always choose a filter rated for at least 1.5 times your tank volume. A tank holding 200 litres should have a filter rated for 300 litres or more. This provides a safety margin and accounts for media becoming partially clogged between cleanings.
Getting Expert Advice
The filter market in Singapore is vast, with dozens of brands and models available across local shops, Shopee and Lazada. Choosing the wrong type wastes money and compromises water quality. Visit Gensou Aquascaping at 5 Everton Park to discuss your specific needs. We can recommend the right filter type, model and media configuration for your tank size, livestock and aquascaping goals, ensuring you get the best performance within your budget.
Related Reading
emilynakatani
Still Have Questions About Your Tank?
Drop by Gensou Aquascaping — most walk-in questions get answered in under 10 minutes by someone who has set up hundreds of tanks.
5 Everton Park #01-34B, Singapore 080005 · Open daily 11am – 8pm
