OASE FiltoSmart Thermo 300 External Aquarium Filter with Heater review

This is a source-based assessment of the current US OASE FiltoSmart Thermo 300, SKU 55165, not a report of ownership, hands-on use or testing. It is a specific filter-and-heater package whose advertised tank ceilings, electrical statements and installation instructions need separate checks.

Thermo 300 is a distinct package, not the standard 300 listing

The US family separates standard FiltoSmart 300 SKU 55162 from Thermo 300 SKU 55165. The Thermo page's included-component cards name the filter body (55162), HeatUp 300 heater (33805) and ThermoFit adapter (48567). That is a functional package difference, not a name or finish alias. Check all three identifiers on the actual listing and package; the standard 300 assessment is the closer comparison if no included heater is wanted. Hiding the heater in the canister reduces separate hardware in the aquarium, but the intake and outlet still occupy tank space.

Read the 80-gallon label as a ceiling, not a range

OASE gives separate “up to” labels of 80 US gallons and 300 litres, but no lower aquarium-volume endpoint. Neither ceiling creates a two-ended range or proves suitability for a particular stocking load. The numeric finder therefore does not certify a volume fit, even at 80 gallons. The maker separately lists maximum flow of 260 GPH / 1000 L/h and adjustable inlet/outlet flow; that is not measured circulation through a particular installation. The page lists 23 W for the filter and the separate heater page 300 W for HeatUp 300, not a measured combined draw.

Included media does not establish a basket capacity

The package page lists a 20-ppi foam, two 10-ppi foams, ceramic and carbon media, intake/strainer, diffuser, spray bar, flow-control adapters, tubing, fittings, base and cables. The North American family manual specifies three 420-g ceramic bags and two carbon bags for the 300-size unit. These details help verify a box, but piece count is not basket capacity.

OASE calls 6.4 L the total filter volume and 1.50 L the prefilter; neither is media-basket volume. No basket litre figure or manufacturer high-waste rating appears in the checked sources, so this package cannot satisfy a hard basket minimum or a requirement for explicit heavy-stock evidence.

Plan the canister location around startup and service

The family manual permits next-to or under placement, so a stable adjacent surface can avoid a below-tank cabinet if the real setup complies. At first startup the connection unit must be no more than 80 cm below the water surface and the outlet must not be submerged; also follow the manual's priming, stable-support, hose and drip-loop instructions. The US product page prints maximum head as both 5.0 ft and 1.30 m, which are not equivalent conversions. Preserve the discrepancy and consult the exact unit instructions instead of silently choosing a value.

OASE lists body dimensions of 11 × 7 × 16.9 in and separately 288 × 179 × 428 mm. Measure the shelf, hose route, outlet position and room to open and service the canister. The page lists an 8-ft hose with 5/8-in ID and a 16/22-mm ID/OD connection table; check supplied fittings before assuming existing plumbing will connect.

Verify the included heater's electrical identity

The separate HeatUp 300 page identifies SKU 33805, 300 W, a 66–90°F scale and a secondary adjustment within ±2°F; OASE also describes bimetal control, thermal shutoff and quartz glass. Its up-to-80-gallon statement is not a guarantee of heating adequacy for every room temperature, target, cover or livestock plan.

The component page conflicts on supply: its specification table says 115 V / 50–60 Hz, but descriptive copy says 230 V. The filter page separately lists 120 V / 60 Hz. Do not infer a single bundle voltage; inspect the included heater label and instructions or confirm with the seller. The manual says not to energize the heater before the filter is full and circulating, and to let it cool before removal. No independent heat, noise, flow or filtration test is claimed.

Who should compare it—and what to check

Compare this bundle when an external canister and included heater are both wanted and a manual-compliant adjacent or under-tank location exists. It is a poor shortcut if the decision requires a lower tank boundary, a basket-litre value, explicit heavy-stock evidence or a voltage answer inferred from web copy. The filter-only standard 300 is the closer package comparison, but it shares the 80-gallon ceiling and 6.4-L total-volume label.

Before ordering, confirm US SKU 55165, filter body 55162, HeatUp 300 SKU 33805 and ThermoFit SKU 48567. Check the physical heater label, box contents, fittings, support and service clearance, and startup/head layout. Assess fish waste and heater demand separately from tank-volume ceilings. The Thermo 200 review covers a distinct smaller package, not an interchangeable model.