







From the brand

How did we get our start?
Here at OASE, we’ve always had a passion for water and for aquatic environments and design that meet the highest possible standards of technical precision – ever since 1949.
Why do we love what we do?
We are designers by trade and composers at heart, both when it comes to creating fascinating water scenes in gardens and aquariums and in the field of professional fountain and water technology.
What makes our products unique?
From idea to implementation, function to fascination, technical to biological: we offer innovative smart products, premium quality and convenience.

Award-winning Products
Reviewed and evaluated by top experts, our products have won international awards for design quality.
Meet our award-winners!

Superior and Reliable Filters
Our quality aquarium filters offer multi-stage cleaning power and long service life to help support a healthy and clean ecosystem.
Meet your new aquarium filter!

Designed with you in mind.
We design our products with unique, helpful features, so you spend less time maintaining and more time enjoying your aquarium!
Product Dimensions : 9.4 x 9.4 x 16.7 inches; 17.15 Pounds
Item model number : BioMaster 2 Thermo 350
Department : All Ages
Date First Available : April 3, 2025
Manufacturer : GeoGlobal
ASIN : B0F3LRD8KK
Best Sellers Rank: #19,714 in Pet Supplies (See Top 100 in Pet Supplies) #86 in Aquarium Filters
Customer Reviews: 4.6 4.6 out of 5 stars (81) var dpAcrHasRegisteredArcLinkClickAction; P.when(‘A’, ‘ready’).execute(function(A) { if (dpAcrHasRegisteredArcLinkClickAction !== true) { dpAcrHasRegisteredArcLinkClickAction = true; A.declarative( ‘acrLink-click-metrics’, ‘click’, { “allowLinkDefault”: true }, function (event) { if (window.ue) { ue.count(“acrLinkClickCount”, (ue.count(“acrLinkClickCount”) || 0) + 1); } } ); } }); P.when(‘A’, ‘cf’).execute(function(A) { A.declarative(‘acrStarsLink-click-metrics’, ‘click’, { “allowLinkDefault” : true }, function(event){ if(window.ue) { ue.count(“acrStarsLinkWithPopoverClickCount”, (ue.count(“acrStarsLinkWithPopoverClickCount”) || 0) + 1); } }); });
OPTIMIZED FLOW & FILTRATION FOR CRYSTAL CLEAR WATER – The next generation of BioMaster has updated features for increased performance. A sealed 4-stage filtration path with multi-density foams, Hel-X Biomedia, and activated carbon delivers superior water clarity for freshwater and saltwater tanks.
THE MOST CONVENIENT CANISTER FILTER ON THE MARKET – The BioMaster’s innovative EasyClean pre-filter module can be removed separately from the rest of the filter. This makes maintenance fast and simple. It also increases filter efficiency and extends the life of main filter foams.
BUILT-IN HEATER – Integrated heater minimizes in-tank equipment, while also protecting inhabitants from direct contact. Temperature controlled via bi-metal technology with a thermal shutoff for safety.
NO-MESS MAINTENANCE – Designed with safety locks on the handle, pre-filter, and aquastop to avoid spills during maintenance. The aquastop is detachable for easy movement of the filter without affecting the tubing setup.
RELIABLE & BACKED BY WARRANTY – Made in Italy, with German engineering from OASE and backed by a 4-year warranty (3 + 1 year with online registration). Includes all the necessary fittings for your setup: curved inlet and outlet tubes, inlet strainer, water outlet nozzle, modular spray bar with flow control attachment, tubing, heater, heater adapter, and 6 ft. power cords (one cord for filter, one cord for heater).
13 reviews for OASE BioMaster 2 Thermo 350 Canister Filter for Aquariums – External Aquarium Filter with Built-in Heater – EasyClean Pre-Filter, Quiet Operation – Freshwater & Saltwater, Up to 90 Gallons
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$309.99
SAM –
Best canister filter out there
I picked up the OASE BioMaster 2 Thermo 250 Canister Filter for my aquarium, and overall it’s been one of the best all-in-one filtration solutions I’ve used, especially for tanks where space and simplicity matter.Right away, the built-in heater integration stands out. Instead of running a separate heater with suction cups and extra cords, this unit heats and filters in one streamlined system. It keeps the temperature stable without hot spots, and the layout looks much cleaner than having multiple devices inside the tank. For anyone who cares about aesthetics and functionality, that combination alone is a huge win.In terms of filter performance, this unit moves water efficiently and handles biological, mechanical, and chemical filtration well. The flow rate is strong without being too aggressive for most community tanks, and the water always looks clear and healthy. I’ve noticed fewer maintenance intervals compared to simpler hang-on filters — the media inside has plenty of capacity and is easy to access when it’s time for a clean.Installation was fairly straightforward. The hoses and connections are solid, and the instruction layout made sense. Once set up, the unit runs quietly and reliably — it doesn’t dominate the room with noise.things to note:The initial price is higher than a standalone filter + heater combo, but in my opinion the integration and convenience justify it.Overall, this OASE BioMaster 2 Thermo 250 feels like a top-tier choice in canister filtration with the added bonus of heating built in. It simplified my setup, performs strongly, and keeps my aquarium water looking great with less fuss — definitely one of the best options I’ve used for mid-size tanks.
cherid –
Great purchase!
So far I am really liking liking the filter. Easy to setup – I watched a few videos on the YouTube to make sure I did everything correctly. Nice and quiet and seems very user-friendly for maintenance. Had to wait a few extra weeks for delivery, perhaps because of the tariff wars, not really sure why. Very happy with this purchase. The tank looks great!
David E. Noles –
Performance
So far, this canister has lived up to its name. The setup was not bad; the only time I ran into trouble was closing the latches back, which was hard and worried me, but I got them to close. I put the rubber mats down to reduce the noise, and we can’t hear it at all, even in the living room. It came with a ton of media, which I rinsed before putting it together. The priming button, or whatever you call it, is amazing to push, and it filled up without an issue. This has been my easiest canister filter setup, and I have used many brands, and by far, this setup was the easiest. I had it set up and working at the 30-minute mark. I am very happy with this purchase. My aquarium is pristine, and I have 2 mature L097 Polka Dot Cactus plecos (not to mention 20 Colombian tetras), and they produce a lot of waste. So far, this canister filter has been effective at removing waste, and the aquarium’s nitrates remain low. It’s pricey, and I got the one with the heater already installed. It performs as expected. Great canister, again a bit pricey, but you get what you pay for.
@!@ –
Worth the money
Very quiet, strong flow, built in heater and pre-filter are nice
Anthony R Koehler –
Great filter.
Love the prefilter on this design. The dock for the in and outflow was a little sticky, but they called that out in the packaging and included a QR code on a video to help with it. The filter is easy to use and service and tightly made. The free bar outflow and inflow and sponge media were never in the cards for me, since I prefer glass lily pipes and other filter media, but it has everything needed to make it work out of the box.
Kindle Customer –
Very quiet
It is as advertised. Quiet. Easy to install. The design is simple with the built in heater. We’ve not had any leaks out of it so far. I’m very pleased with this filter and I will be buying another one for our second setup. 100% recommend.
Golddiggerjoe –
Pree filter a must.
Love it, to me it’s worth the price because of the pree filter, also the internal heater.
Kaeleigh Tilley –
Amazing filter, little less flow than desired for the price
Best filter of all time. Extremely easy to clean, with the pre filter makes this canister filter worth it. I did wish it had better flow for the price, but cannot complain with the media and heater inside of the canister filter.
Alrick –
This was my first time using an external filter and after all my research this was my best opinion. Low maintenance and takes up less space and super quiet
Krista Belisle –
Love this canister filter. Have used several other high end brands in the past but the Oase biomaster 850 is the best so far. The ease of use, cleaning, and startup is excellent. Have 2 of these and one Oase filtosmart 200. I recommend all of these filters you will love any of them.
Florin Mot –
As I couldn’t ask the sender in a private message I will like to ask if this filter it is working just from time to time and not continuously filtering the water. It stays off for 2 min and then for about 10 sec I can hear a sound that is filtering. Is it normal?
Pierre Armirotto –
Vroegtijdig geleverd maar tiptop in orde
Francesco –
Molto efficente