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OASE

OASE Indoor Aquatics Biomaster Thermo 350

  • Based on 241 reviews
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Arrives Monday, Jul 7
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Style: Biomaster Thermo 350


Features

  • The Bio master thermos 350 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 350 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. Add the included diffuser for uniform surface movement and provides additional dissolved oxygen to the water for ideal water quality. 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. 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 16.7"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: 216 watts


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 9.4 x 9.4 x 16.7 inches; 12.57 Pounds


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ 55149


Date First Available ‏ : ‎ December 19, 2018


Manufacturer ‏ : ‎ OASE


Best Sellers Rank: #42,378 in Pet Supplies (See Top 100 in Pet Supplies) #525 in Aquarium Filter Accessories


#525 in Aquarium Filter Accessories:


Customer Reviews: 4.3 4.3 out of 5 stars 241 ratings


Brand: OASE


Product Dimensions: 9.4"W x 16.7"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: 216 watts


Voltage: 120 Volts


Maximum Flow Rate: 1.1E+3 Liters Per Hour


Efficiency: High


Style: Biomaster Thermo 350


Mounting Type: None/Not Applicable


Is Electric: Yes


Manufacturer: OASE


Item Depth: 16.7 inches


UPC: 706759551496


Global Trade Identification Number: 96


Item Weight: 12.57 pounds


Item model number: 55149


Date First Available: December 19, 2018


Item Package Dimensions L x W x H: 18.1 x 14.4 x 11.4 inches


Item Dimensions LxWxH: 9.4 x 9.4 x 16.7 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: 55149


Size: 16 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: Monday, Jul 7

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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Similar Products

Top Amazon Reviews

    • Next Level - Just Buy It
Style: Biomaster Thermo 350
One of the coolest things ive bought for my freshwater planted tank. The Oase Biomaster 350 is a beast and a QUIET one at that, I have powerheads louder than this thing and I have to touch it to see if its on. The only thing I was disappointed with was that only one bag of bio media is included, the rest are sponges - so I added Seachem Matrix to two of the other trays along with the included biomedia. If youre feeling fancy you can opt for the Aquario Neo Lily pipes size large but the stock pipes are fine, just not as fancy. Water flow is good, a little more mellow than I expected with the spray bar, build quality is exceptional, easy to setup and go and the self siphoning feature is gold. Great price right now too, I have the UNS Delta 90 and it was cheaper than the Oase but the Biomaster is almost twice the capacity and quieter. Wish I'd gone Oase all the way. ... show more
Reviewed in the United States on June 3, 2025 by PhotoB
    • Perfection
Style: Biomaster Thermo 350
I've had this filter for 2 months now running on my african cichlid tank. I went through sisse, fluval and now Oase. The Sisse was one the worst filter I've ever had the displeasure of using. It was incredible hard to get started, just for it to quick working hours later, speaking with Jay, the rep was even worse and was no help. money down the drain. The fluval worked for about a month, constantly clogged, and then the top started coming lose. luckily I was home when it happened... the second time, it drained my tank and flooded my room..... Fluval was no help to me. This Oase has been the easiest to assemble, the most quiet, and i do enjoy the built in heater. So far it's been a win.. if anything changes, I'll update this review ... show more
Reviewed in the United States on May 19, 2025 by Ryan
    • One of the best
Style: Biomaster Thermo 350
Extremely silent! Super easy to get it going. If I had to come up with a reason to dislike it I could say the tubes are a bit thick so it’s hard to keep them still, but you can replace it. Working great so far!
Reviewed in the United States on June 11, 2025 by Jon B.
    • Super quiet. Great filter.
Style: Biomaster Thermo 350
For some reason I was hesitant to spend the money on this but glad I did. The pre-filter is a little to fine of a sponge but that's a pretty easy fix if I want. Super quiet. Would recommend.
Reviewed in the United States on May 11, 2025 by J
    • I love this filter!
Style: Biomaster Thermo 350
Review Image by Argusi Argusi
Let's get the negative out of the way first. When I received this, one of the rubber gaskets internally was torn, so I emailed Oase support with photos asking for a replacement gasket as I didn't want to return the entire product and hold up my aquarium build. I received the automatic confirmation email back, but never received an reply. After 2 weeks, I emailed again. They then promptly replied and said that the gasket was on back order and would not be available for another 4 months. They suggested I return it and get a new filter. I looked at it and didn't think it would cause any leakage, but thought it may lower the throughput of the filter. I chose to go with it and replace it at a later time at my own expense. Hopefully they won't make me purchase a new pre-filter assembly. The filter is working just fine. This made it a 4 star. If the gasket was good, I 100% would have given 5 stars... The only other thing I don't really like about the filter is the intake/output design. There are a few other cannister manufacturers out there that make the transition from hose to tank a bit nicer. The squarish fittings over the top of the tank are kind of floppy, only to have 1 suction cup on the output and 2 suction cups on the intake barely helping to hold it in place. This is compounded by the fairly stiff hose makes for a bit of a twisting bending moving activity to get everything to sit right on the tank. Don't get me wrong, it works, but I'm just saying it could be designed a little better. Now for the good. I pretty much like everything about the cannister. The pre-filter and ease of access. The integrated heater. The build quality and design. I did cut up one of the blue coarse filters to use on the pre-filter instead of using the finer sponge that came with it, but that's personal preference. Internally, I used the coarse filter on the bottom (1st media. Flow is bottom to top in the main part of the filter) the fine filter at the top and biomedia between them. Overall, I am extremely happy with this purchase and unless something catastrophic occurs, I will probably be using these exclusively in the future. I whole heartedly recommend this filter. ... show more
Reviewed in the United States on January 17, 2023 by Argusi Argusi
    • Amazing filter
Style: Biomaster Thermo 350
Review Image by laura pannella laura pannella
Review Image by laura pannella laura pannella
This filter is crazy quiet, water flow is the best I’ve seen yet. The filter is easy to set up, and seems almost over engineered … I have the spray bar set up to agitate the water surface , you can adjust the angle to suit your preference … Might need to figure out how to get the intake and output brackets, to fit my tank better, but other than I recommend this filter to everyone, anyone and people in between … Best filter I have ever had … Will adjust as needed if anything changes ... show more
Reviewed in the United States on January 1, 2025 by laura pannella laura pannella
    • Still works great
Style: Biomaster Thermo 350
I have had this up a running for a few years. The heater keeps the water warm. Right now it is on a 75gal tank with a few Oscar's and I have had no water quality issues at all.
Reviewed in the United States on February 21, 2025 by Wolfspire
    • Look like a great design, but the function is severely lacking.
Style: Biomaster Thermo 350
I liked the fact of how easy it was to clean the pre-filter section and I liked the fact that the heater is built-in but it never filtered all the particles out of the fish tank because it keeps on getting air bound and each time it purges it disturbs all the matter in the filter, sending it all back into the tank. I worked on it and I finally got it so it didn't suck air in so I thought everything was going to be better, but it never filtered out all the finer particles. After several months, I was done with it and purchased a Fluval. Overnight, I could see a big difference and after several days I am very happy with the results of my new filter by Fluval. A $300 learning experience. ... show more
Reviewed in the United States on March 7, 2024 by Joseph Kuiper

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