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OASE

OASE Indoor Aquatics Biomaster Thermo 250,Black

  • Based on 284 reviews
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Availability: Only 3 left in stock, order soon!
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Arrives Wednesday, Sep 10
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Style: Biomaster Thermo 250


Features

  • The Bio master thermos 250 has an integrated heater in compact Filter design
  • The built-in heater provides your aquarium with Precise and uniform temperature levels while the product integration delivers unobstructed views of your Aquarium
  • External filter operates quietly to circulate and filter your aquarium water
  • Includes 4-stage filtration: biological, mechanical, chemical, and prefiltration
  • Hel-x, suspended Filter media, creates the optimal surface area for beneficial bacteria growth

Description

The biomaster Thermo line of premium external filters with integrated heaters are perfect for marine and freshwater aquariums. The biomaster Thermo 250 boasts 4-stage filtration in a compact design. With the heater integrated into your filter, there is more room for undisrupted beauty in your aquarium. Biological, mechanical, chemical, and prefiltration all work together to provide your aquarium with optimal water quality and clarity. The biomaster filters are designed with sealed filtration pathways to ensure water flow is getting the full benefits of prefiltration, filter media for clearer water, hel-x biomedia provide a large suspended settlement surface for microorganisms, and activated carbon for ideal nutrient reduction and removal of toxins. The easy clean pre-filter module can be removed and cleaned separately from the rest of the filter for high efficiency and to extend the life of your filter. The water flow Can easily be adjusted on both the inlet and outlet adapters for the filter. Created for convenient placement under the aquarium. Install the included diffuser and spray bar for uniform surface movement and additional dissolved oxygen for ideal water quality. This filter Also features a N handle for simple moving and maintenance. This energy- efficient design includes a self-priming function for easy operation on startup and after cleaning. Includes a shut-off automation with built-in check valve to prevent leakage when cleaning the filter. Designed using German engineering and manufactured in Italy, this quiet operating filter is supported by an included 3 year warranty with a free 1 year warranty extension with online product to customize your pre-filter by combining coarse, Fine, ultra Fine, and activated carbon filter foams.

Brand: OASE


Product Dimensions: 9.4"W x 14.6"H


Special Feature: The EasyClean prefilter module can be removed separately from the rest of the filter for simple cleaning and to extend the life of your filter, Adjustable flow control is built into the inlet and outlet of the filter, The sealed filtration pathway allows you to get the full benefits from all 4-stages of filtration See more


Color: Black


Wattage: 165 watts


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 9.4 x 9.4 x 14.6 inches; 11.46 Pounds


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ 55148


Date First Available ‏ : ‎ December 19, 2018


Manufacturer ‏ : ‎ OASE


Best Sellers Rank: #42,406 in Pet Supplies (See Top 100 in Pet Supplies) #526 in Aquarium Filter Accessories


#526 in Aquarium Filter Accessories:


Customer Reviews: 4.4 4.4 out of 5 stars 284 ratings


Brand: OASE


Product Dimensions: 9.4"W x 14.6"H


Special Feature: The EasyClean prefilter module can be removed separately from the rest of the filter for simple cleaning and to extend the life of your filter, Adjustable flow control is built into the inlet and outlet of the filter, The sealed filtration pathway allows you to get the full benefits from all 4-stages of filtration


Color: Black


Wattage: 165 watts


Voltage: 120 Volts


Maximum Flow Rate: 2.5E+2 Gallons Per Minute


Heat Output: 1.5E+2 Watts


Efficiency: High


Maximum Pressure: 2.86 Pound per Square Inch


Mounting Type: Floor


Is Electric: Yes


Manufacturer: OASE


Item Depth: 14.6 inches


UPC: 706759551489


Global Trade Identification Number: 89


Item Weight: 11.46 pounds


Item model number: 55148


Date First Available: December 19, 2018


Item Package Dimensions L x W x H: 17 x 15.38 x 12 inches


Item Dimensions LxWxH: 9.4 x 9.4 x 14.6 inches


Brand Name: OASE


Target Audience Keyword: fish, Fish


Directions: As directed on packaging


Country of Origin: Italy


Warranty Description: 3 year limited + 1 year warranty extension with online registration


Model Name: 55148


Size: 15 W / 9.4 IN


Age Range Description: All Life Stages


Number of Items: 1


Included Components: Aquarium Filter with heater, filter media, tubing, intake and outflow tubes, diffuser, spray bar, fittings, and power cable


Specific Uses for Product: Indoor


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Sep 10

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Oase bio master 250
Style: Biomaster Thermo 250
I just received my bio master 250 from oase. I thrilled at how easy it was to set up and well it was put together. Wonderful quality, and so very quiet. This is by far the best filtration system I have ever owned.
Reviewed in the United States on May 19, 2025 by Curtis A White
    • Great for Saltwater Reef Tank
Style: Biomaster Thermo 250
The Oase Thermo Biomaster 250 canister filter has truly impressed me with its performance and features. Here are the key points I found noteworthy: Design and Build Quality: The filter is well-constructed, featuring a sturdy design that feels durable. The compact size makes it easy to fit in tight spaces, especially in my cabinet. The integrated heater is a game-changer, eliminating the need for an additional heater in the aquarium. Ease of Installation: Setting up the Thermo Biomaster was straightforward. The user manual was clear, and all necessary parts were included. The quick-release valves make it easy to detach the filter for maintenance without creating a mess. Performance: This filter provides excellent water clarity and quality. The three-stage filtration system (mechanical, biological, and chemical) works effectively to keep my tank pristine. The adjustable flow rate allows for customization based on the needs of my aquarium, which is a nice touch. Though I keep the flow rate fully open. Heater Integration: Having a built-in heater is incredibly convenient. It maintains stable temperatures, which is essential for aquatic life. The heater is reliable and adjusts quickly to changes, ensuring a comfortable environment. Maintenance: Maintenance is a breeze with the easy-access filter media trays. I appreciate the reminder for maintenance intervals, which helps me stay on top of cleaning without guesswork. Noise Level: I found the noise level to be minimal, especially compared to some other filters I've used. Conclusion: Overall, the Oase Thermo Biomaster 250 is an outstanding canister filter that combines effective filtration with convenient heating. It’s perfect for aquarists looking for a reliable solution for their tanks. I would highly recommend it to anyone looking to enhance their aquarium setup! ... show more
Reviewed in the United States on October 19, 2024 by ME
    • Looks like it will work well for a tank smaller than 55 gallons
Style: Biomaster Thermo 250
Bought this as a used like new unit for a 55 gallon tank saltwater tank. It looked very used and dirty so it was sent back, but it looked like a solid unit. The heater seemed small for heating a 55 gallon tank, but honestly I never set it up out of concern for how dirty it was. I ended up buying a Fluval canister unit and separate heater ... show more
Reviewed in the United States on June 28, 2025 by Codfish
    • Easy assembly, Whisper Quiet!
Style: Biomaster Thermo 250
Review Image by CLINKC CLINKC
Review Image by CLINKC CLINKC
Easy to put together, so quiet my little air pump is all you hear now. Immediately cleaned up my tank, strong current. Only thing that is off is the little diverter of you use that rather than spray bar included. The tip blew off so I just left it off. Easy to angle outflow. Plenty of circulation, fits well in the aquarium stand. Highly recommend over power filter that hangs on the back. ... show more
Reviewed in the United States on April 13, 2025 by CLINKC CLINKC
    • Extremely Quiet and Efficient
Style: Biomaster Thermo 250
The media could not be loaded. Great filter. Extremely quiet. Much quieter than the hanging filters. Having the ability to adjust the flow rate for different tank options is desirable. Cleaning the installed filters can take some getting used too but it isn't too difficult. Fish seam to have adapted well to new filter. ... show more
Reviewed in the United States on April 27, 2025 by Frank M.
    • Best Canister Filter Ever!
Style: Biomaster Thermo 250
Review Image by Samuel A. Samuel A.
Review Image by Samuel A. Samuel A.
I LOVE IT! I've been using two of these Thermo 250's on my freshwater 55 gal, for 3 weeks+ now. The Thermo 250 cost a lil more than most canister filters, but has 2 great features that make it worth the extra price. 1: It comes with a built in heater which is great, because that's less clutter in your aquarium. 2: It has a pre-filter on the intake that can be pulled out and cleaned separately, so you don't have to always clean the whole canister, and you can keep that good bacteria growing in the main filter trays. 3: It comes with 4 trays to add media too. 4: It's super quiet, my 60 gal rated air pump is louder then both of my 250Ts combined, and the air pump really quiet. I have not had to do any maintenance in my first month of running and the water flow is still very strong in my heavily fish stocked/planted aquarium. I have to be honest though; I'm only using the coarse circular intake filter pads that came with it, because I upgraded just about everything else. I also added jardli glass water intake and glass water outtake for that kool less clutter look. This is because I did some serious research on the net and good ol youtube. After a long search on all types of aquarium filters ie.. hang on back, canister, sponge, under gravel and sup, I came across this Thermo 250 Canister from Oase. Now just about all if not every youtube video on it was from a none english speaking country. Then I seen this random video that said "pimpmyfilter". I clicked on it and some British guy named the "pondguru" was giving a demonstration on how to make the Thermo 600 model more efficient. After watching that video I was completely hooked/sold on his way of making the Thermo Canister filter more efficient. I didn't do the drilling though, cause it doesn't seem to be needed, the water flow is still very strong. With that being said I can't give an honest opinion on how good the filter media is that came with it like the meduim and fine pads and the ceramic balls. Because, I pimped out both of my Thermo 250s from start. I am using the original black fine pads for the prefilter, because they work the best for trapping muck and not letting it through to the main filter. No matter what type of filter you get whether it's this one or another model or brand, I highly highly recommend that you go on YouTube and type "pimpmy(filter name here)filter" ie pimpmyoasethermofilter, pimpmyfluvalfilter, pimpmywhateverfilter. I promise you that that will be the most helpful thing you ever did when it comes to searching for and aquarium filter. No-one on the internet that I've seen is doing anything remotely close to what that guy does to aquarium fliters. He didn't pay me or ask me to promote his channel. He'll probably never know that I'm promoting his work. I'm just giving him mad props because he deserves it. Watch and see, and I bet you'll come back looking for this review to say that it really helped you. ... show more
Reviewed in the United States on January 29, 2020 by Samuel A. Samuel A.
    • Damaged product
Style: Biomaster Thermo 250
Received a used and damaged product. Box was open filter compartment had water inside it. Whom ever had it prior had plugged in the heater prior to putting water in it and melted the plastic of the baskets where the heater goes.
Reviewed in the United States on June 29, 2025 by Andrew A.
    • GREAT!
Style: Biomaster Thermo 250
Great filter it's actually quieter than my HOB filter it is replacing (no not water quiet operation quite).
Reviewed in the United States on April 24, 2025 by Vicki Olson

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