# Fluval FX6 Canister Filter vs OASE BioMaster Thermo 850 Canister Filter: specs and price compared

A sourced, side-by-side comparison of the Fluval FX6 Canister Filter (Fluval) and OASE BioMaster Thermo 850 Canister Filter (OASE) among aquarium filters.

## Side by side

| Spec | Fluval FX6 Canister Filter | OASE BioMaster Thermo 850 Canister Filter |
| --- | --- | --- |
| US price | $369.99 | not published |
| Brand | Fluval | OASE |
| Type | canister | canister |
| Flow rate gph | 925 | 400 |
| Tank size gal | 400 | 250 |
| Media capacity (L) | 5.9 | 8 |
| Media stages | 3 | 4 |
| Wattage | 43 | 32 |
| Self priming | Yes | Yes |
| Dimensions (in) | 15.75 x 15.75 x 20.8 | 9.4 x 9.4 x 21.1 |

## Key differences

- Flow rate gph: Fluval FX6 Canister Filter 925 vs OASE BioMaster Thermo 850 Canister Filter 400
- Tank size gal: Fluval FX6 Canister Filter 400 vs OASE BioMaster Thermo 850 Canister Filter 250
- Media capacity (L): Fluval FX6 Canister Filter 5.9 vs OASE BioMaster Thermo 850 Canister Filter 8
- Media stages: Fluval FX6 Canister Filter 3 vs OASE BioMaster Thermo 850 Canister Filter 4
- Wattage: Fluval FX6 Canister Filter 43 vs OASE BioMaster Thermo 850 Canister Filter 32
- Dimensions (in): Fluval FX6 Canister Filter 15.75 x 15.75 x 20.8 vs OASE BioMaster Thermo 850 Canister Filter 9.4 x 9.4 x 21.1

## Sources

- Fluval FX6 Canister Filter: https://www.fluvalaquatics.com/us/shop/product/fx6-canister-filter-up-to-400-us-gal-1500-l (fluvalaquatics.com, verified 2026-08-01)
- OASE BioMaster Thermo 850 Canister Filter: https://www.aquaristikshop.com/aquaristik/OASE-Aussenfilter-BioMaster2-Thermo-850/788008/ (aquaristikshop.com, verified 2026-08-01)

Canonical: https://frontdeskreview.com/gear/aquarium-filters/fluval-fx6-vs-oase-biomaster-thermo-850/
Cite: Per The Front Desk Review, Fluval FX6 Canister Filter ($369.99) vs OASE BioMaster Thermo 850 Canister Filter (not published) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/aquarium-filters/fluval-fx6-vs-oase-biomaster-thermo-850/
License: CC BY 4.0.