OASE FiltoSmart Thermo 100 – External Canister Filter with Heater (up to 100L)

The OASE FiltoSmart Thermo 100 is a compact external canister filter with a fully integrated heater, purpose-built for aquariums up to 100 litres. It merges two pieces of essential equipment — biological/mechanical filtration and precise water heating — into a single unit that sits quietly out of sight, typically in a cabinet below the tank. The result is a cleaner-looking aquarium with one less cable, one less piece of glass, and one less thing to think about.

What Makes It Different

Most starter aquariums run a canister filter and a separate glass heater side by side, competing for space and both needing their own mounting, cabling, and cleaning routine. The FiltoSmart Thermo 100 folds the heater directly into the filter housing, so water is heated as it passes through the filtration chamber rather than at a single point in the tank. That means more even heat distribution and one fewer piece of visible hardware inside the aquascape — a real advantage for planted tanks and nano/community setups where every centimetre of glass matters visually.

OASE also engineered the unit around maintenance speed. The EasyClick lid opens without tools, the inlet and outlet lock shut before you disconnect the hoses so nothing drips on the way to the sink, and the filter self-primes on startup — no manual siphoning required to get water flowing.

Key Benefits

• Space-saving 2-in-1 design — combines an external filter and an integrated HeatUp heater in one housing, freeing up visible tank space
• Even heat distribution — water is warmed as it flows through the filter media rather than at a single hot spot
• 2-stage filtration — mechanical pre-filtration through 20 ppi and 10 ppi foam, followed by biological filtration through ceramic media
• Tool-free maintenance — EasyClick opening mechanism for fast lid access during service
• Spill-free servicing — locking inlet/outlet adapters shut off automatically when disconnected
• Self-priming startup — no manual siphoning needed to get the filter running
• Adjustable flow control — fine-tune flow independently at the inlet and outlet
• Quiet, sound-dampened housing — suitable for living rooms and bedrooms
• Freshwater and marine compatible
• 3-year manufacturer warranty — OASE's standard coverage on this product line

Technical Specifications

• Max. recommended aquarium volume: 60–100 L
• Max. flow rate: 600 l/h
• Filter power consumption: 11 W
• Integrated heater output: 100 W (HeatUp heater)
• Combined power consumption: 111 W
• Nominal voltage: 230 V / 50 Hz
• Dimensions (W x D x H): 192 x 190 x 312 mm
• Filtration stages: 2-stage — mechanical and biological
• Filter media included: 20 ppi foam, 10 ppi foam, ceramic biological media
• Warranty: 3 years

Who Should Use This

The FiltoSmart Thermo 100 is built for aquarists running a single tank between roughly 60 and 100 litres — think nano and small community setups, low-tech planted tanks, betta or shrimp aquariums, and small marine or brackish setups. It suits anyone who wants a tidy under-cabinet install rather than a visible in-tank heater, and anyone who's tired of running two separate pieces of equipment that both need their own maintenance schedule. It's not intended as the primary filtration for tanks meaningfully larger than 100 L — for those, the FiltoSmart Thermo 200 or 300 in the same range is the better fit.

Setup & Maintenance

Position the filter below or beside the aquarium, ideally in a cabinet, at or below water level so gravity assists priming. Connect the intake tube with the inlet strainer and the spray bar or nozzle on the outlet, then open both flow control valves and start the filter — the self-priming function draws water through without manual siphoning. Set the integrated heater to your target temperature and allow a few hours for the reading to stabilize before fine-tuning.

1. Rinse new filter media in aquarium water (never tap water) before first use to avoid killing beneficial bacteria.
2. Check flow rate weekly for the first month as the biological media matures.
3. Open the EasyClick lid every 4–6 weeks to rinse mechanical foam; avoid replacing all media at once to protect the bacterial colony.
4. Wipe down the intake strainer if flow noticeably drops — this is usually the first sign of a partial clog.

Expert Tip

Don't rinse the ceramic biological media and both foam stages on the same day. Stagger your cleaning — foam this week, ceramic media a few weeks later — so you're never wiping out your entire bacterial colony in one sitting. This single habit prevents most of the mini-cycles and ammonia spikes that catch people off guard after "just doing routine maintenance."

Frequently Asked Questions

Does the integrated heater replace a separate aquarium heater completely?

Yes — the HeatUp heater is fully integrated into the filter housing and is designed to be the sole heat source for the aquarium, eliminating the need for a separate in-tank heater.

Is this filter suitable for a marine or reef tank?

Yes, OASE lists the FiltoSmart Thermo 100 as compatible with both freshwater and marine aquariums.

How often do I need to clean the filter?

Most aquarists rinse the mechanical foam stages every 4–6 weeks and check the ceramic biological media less frequently, adjusting based on bioload and how quickly flow rate drops.

Can I run this filter without the heater switched on?

Yes, the filtration and heating functions operate independently, so you can run pure filtration if your room temperature already suits your livestock.

What's the difference between the FiltoSmart Thermo 100, 200, and 300?

The main difference is heater output and recommended tank volume — the 100 is rated for aquariums up to 100 L, while the 200 and 300 scale up for larger tanks. Filtration principles and build quality are shared across the range.

Pairs Well With

• Ziss CO₂ Generation Kit ZCR-160 — a compact bio-CO2 system sized for tanks up to roughly 120 L, a natural match for planted setups running this filter
• MasterLine All In One Boost — a complete liquid fertilizer for planted aquariums that pairs well with the stable water flow and temperature this filter provides
• OASE FiltoSmart Thermo 200 — worth considering if you're planning to upgrade to a larger aquarium down the line