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OASE Indoor Aquatics Biomaster

  • Based on 150 reviews
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Availability: Only 4 left in stock, order soon!
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Arrives Wednesday, Dec 25
Order within 18 hours and 35 minutes
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Style: Biomaster 250


Features

  • 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
  • The sealed filtration pathway allows you to get the full benefits from all 4-stages of filtration
  • The easy clean prefilter module can be removed separately from the rest of the filter for simple cleaning and to extend the life of your filter
  • All Life Stages

Description

The biomaster line of premium external filters are perfect for marine and freshwater aquariums. The biomaster 250 boasts 4-stage filtration in a compact design. 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.


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 9.4 x 9.4 x 14.6 inches; 11.2 Pounds


Item model number ‏ : ‎ 55145


Date First Available ‏ : ‎ May 31, 2018


Manufacturer ‏ : ‎ OASE


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Dec 25

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


  • New 75G Aquarium Setup
Style: Biomaster 350
Upgraded from 55G to 75G Aquarium tank. Replaced existing external filters with OASE Biomaster 350. Set up was very easy and our new aquarium is crystal clear. Also the tank is located in a living room of our house and the filter is extremely quiety! Would recommend to anyone looking to convert to a canister filter. ... show more
Reviewed in the United States on April 30, 2019 by Lakersfan2282

  • Review updated 3 20 2020
Style: Biomaster 250
I'm using this 250 on an all in one converted reef tank that now is a planted shrimp tank. Here are some observations: 1. Well made, great design and quiet (except for the annoying air bubbles, purging that happens with regularity. Not sure what I can do about the air bubbles as it probably is a design flaw that wont go away.) 2. Instruction inefficient. Thank God for YouTube or I would have returned it as a damaged unit even though it is not. The open and close toggle arm to remove the chamber will not allow you to turn it to the open position unless the other one where you add your intake and out hoses is already in the open position, so do not attempt to turn it or you could break it. I almost did. 3. Love the simplicity of cleaning it! That first chamber is what traps most of the debris and can so easily be taken out and cleaned weekly! Awesome. 4. If power goes out you dont have to worry about this thing needing a prime, works right away and is very quiet and small factor. 5. This (American) model doesnt allow you to put a heater it in, I personally dont care but just an fyi. 6. Air bubbles... If you hate purging of air and air bubbles dont buy Overall I like this thing. I DONT feel badly giving it 2 out of 5 stars BUT I do NOT at all regret the purchase and it has made my water crystal clear but it has some annoying issues that I have no solution for yet. You will not be disappointed with the 250. I use it on my 26 gallon and it is adjustable but I feel it's perfect for my betta shrimp setup. Wish air bubbles were not so prominent. Update 3/20/20: the noise from trapped air inside the container is still there but not as bad. Also the water is crystal clear. Love this thing but it scares my cats with the weird noises... Update 9/22/20: Well I have a much cheaper hang on the back filter coming today from Amazon. This OASE proved to be a huge waste of money. Unfortunately the pump stopped working efficiently and could not pull/push water at all. I took it the top apart cleaned everything multiple times changed the intake and outtake lines shortened them etc etc. luckily Amazon is quick to ship out replacements or my fish might be suffering from this weak piece of equipment. I went to the oase site to try and find a replacement pump with no success. ... show more
Reviewed in the United States on March 4, 2020 by Stylianos Stylianos

  • Great Filter, easy to maintain
Style: Biomaster 250
As a Ehiem user for many years I decided to make the move. This filter with the easy removeable pre-filter is an industry game changer. As you do your weekly water changes, you can easily take out the pre-filter without opening up the main body of the filer and just rinse out the sponges in tap water as it is your pre-filter and you are not touching your main body that houses all your biological media. I have this filter for about 2 months now. I do weekly pre-filter cleaning haven't touch the main filter chamber. There is also a spot for a Oase heater in the filer so it does not have to go in the tank. To me, there is great flow and it is dead silence comparable to the Ehiems. ... show more
Reviewed in the United States on September 13, 2020 by Sean G Nunes

  • Great filter, easy cleaning and silent
Style: Biomaster 350
Ive been eyeing these for about a year and so glad they are available here in the States. Light, silent and best of all you can clean the mechanical portion with out opening the unit up!
Reviewed in the United States on January 24, 2019 by Steven R Burdick

  • Easiest filter to maintain
Style: Biomaster 350
This probably is the BEST filter I have used in the last 15 years of me bing in the fishkeeping hobby. Maintenance of this filter is just so easy. The prefilter comes right out with the twist of a lever. You can clean it with tank water or running tap water. You don't have to pull apart the whole filter to clean it. Many people used to use separate pre-filters on their canister filters. Those times are gone. Also, this has just a LOT of space for media. They sent a bunch of media with it but I replaced most of it with Seachem matrix. I run this on a 40B that hold a batch of 10 Peckoltia compta. They eat a lot and they poop a lot. This filter deals with all of it like a champ. Also, the spray bar is AMAZING! Eheim etc. have spray bar as well but the newer Fluvals/Marineland etc. don't. No spraybar is a deal breaker for me. I have pointed my spraybar to the surface of water and it keeps a lot of surface agitation which helps with dissolved oxygen AND protein film on the surface. Also, did I say that my 40B is at 8 feet height? Yup. I have a 3 tier rack system in the fishroom and the third level is about 8 feet high including tank height. This beast pushes water without ANY problems. Overall an A+ product. You won;t be dissatisfied with this. ... show more
Reviewed in the United States on September 21, 2020 by Summer T.

  • Excellent!
Style: Biomaster 250
Love everything about it.
Reviewed in the United States on May 20, 2019 by Leonard H.

  • Needs better instruction manual!
Style: Biomaster 600
Update: I was hesitant to add the rubber feet that were included, knowing the extra friction would make it harder to slide the filter out from the cabinet under my fish tank; However, after seeing reviews on how much those feet made a difference in reducing noise, I caved in and stuck on the feet. Yes, it’s going to be harder to shimmy the filter out during my bi-weekly cleanings, but the filter is now virtually silent. Changed my rating to 5 stars. **************************************************** I purchased this because my Eheim canister was very inconsistent. Overall the Biomaster 600 is not bad so far, but I’ve only had it running for a couple days. I have a 65 gallon and got the 600. I was hoping for a stronger flow but it’s adequate and stronger than my previous Eheim, even at its best. My water is still a little cloudy from a water change but it’s gradually clearing up after setting up the Biomaster. Love the removable prefilter function, makes cleaning much simpler. It’s not as quiet as I expected, maybe still has some air stuck in it. One thing that really needs to be improved is the instruction manual. I know it’s translated from Italian or German, but its all over the place. You have to press down on the prefilter “knob” to get the filter flow started, and this was barely mentioned in the manual! ... show more
Reviewed in the United States on November 25, 2020 by Mikey

  • Pre filter is the best feature of this filter
Style: Biomaster 600
Nothing to not like. This thing is a Mercedes… Worth every penny. And the Pre filter is so convenient.
Reviewed in the United States on September 30, 2021 by Luis M.

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