---
product_id: 327911721
title: "OASE Indoor Aquatics Biomaster Thermo 250,Black"
brand: "oase"
price: "6664 kr"
currency: DKK
in_stock: false
reviews_count: 5
category: "Oase"
url: https://www.desertcart.dk/products/327911721-oase-indoor-aquatics-biomaster-thermo-250-black
store_origin: DK
region: Denmark
---

# 4-stage filtration for crystal clear water Whisper-quiet operation Integrated heater for precise temp OASE Indoor Aquatics Biomaster Thermo 250,Black

**Brand:** oase
**Price:** 6664 kr
**Availability:** ❌ Out of Stock

## Summary

> 🔥💧 Quiet power meets sleek design — your aquarium’s new heartbeat!

## Quick Answers

- **What is this?** OASE Indoor Aquatics Biomaster Thermo 250,Black by oase
- **How much does it cost?** 6664 kr with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.dk](https://www.desertcart.dk/products/327911721-oase-indoor-aquatics-biomaster-thermo-250-black)

## Best For

- oase enthusiasts

## Why This Product

- Trusted oase brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Custom Flow Control:** Adjust inlet & outlet flow for perfect water circulation
- • **Engineered for Peace:** German design, Italian build, ultra-quiet with 3-year warranty + 1-year extension
- • **Effortless Maintenance:** EasyClean pre-filter module removes separately to preserve beneficial bacteria
- • **Quadruple Filtration Power:** Biological, mechanical, chemical & prefiltration for pristine water quality
- • **Seamless Aquarium Elegance:** Integrated heater + filter = zero clutter, max viewing pleasure

## Overview

The OASE Indoor Aquatics Biomaster Thermo 250 is a premium external aquarium filter with an integrated heater, delivering precise temperature control and 4-stage filtration (biological, mechanical, chemical, prefiltration) in a compact, quiet design. Featuring adjustable flow, an easy-clean pre-filter, and engineered with German precision and Italian craftsmanship, it ensures crystal-clear water and optimal aquatic health while maximizing aquarium aesthetics. Backed by a 3-year warranty plus a free 1-year extension, it’s the ultimate all-in-one solution for freshwater and marine tanks.

## 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.

Review: 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.
Review: Really good external canister filter. I set this up for my 40 gal planted aquarium. I use two of the trays for bio medium, one for sponge and the last one with purigen. My water is crystal clear. Filter is very quiet. I am going to leave the main filter running for a few months but clean the pre filter every month as the pre filter can be easily taken out without dismantling the whole filter. The built in heater is very accurate. Now my tank has lots of room for aquascaping as before I had a Fluval submersible filter plus a heater. At first I thought I can save some money and get Oase without the heater but I heard fish can get burns bumping into the heater, I decided to get the thermal version and have not regretted it. I watched a lot of videos on different canister filters before buying this. All of Green Aqua's aquariums have this filter. Well built filter. Some day I might change the output to a Lily pipe but for now I use the included accessory to get surface agitation.

## 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

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B07LHD941X |
| ASIN  | B07LHD941X |
| Batteries Included? | No |
| Batteries Required? | No |
| Best Sellers Rank | #60,884 in Pet Supplies ( See Top 100 in Pet Supplies ) #3,521 in Aquarium Accessories |
| Color | Black |
| Customer Reviews | 4.3 4.3 out of 5 stars (276) |
| Customer reviews | 4.3 4.3 out of 5 stars (276) |
| Date First Available | 7 January 2019 |
| Date First Available  | 7 January 2019 |
| Flow Rate | 250 Gallons Per Minute |
| Included components | Aquarium Filter with heater, filter media, tubing, intake and outflow tubes, diffuser, spray bar, fittings, and power cable |
| Is Discontinued By Manufacturer  | No |
| Item Package Quantity | 1 |
| Item Weight | 5.2 Kilograms |
| Item model number | 55148 |
| Item model number  | 55148 |
| Manufacturer | OASE |
| Manufacturer  | OASE |
| Material | Stainless Steel |
| Maximum Pressure | 8 Bars |
| Part number | 55148 |
| Plug Profile | Wall |
| Power source type | Corded Electric |
| Product Dimensions | 23.88 x 23.88 x 37.08 cm; 5.2 kg |
| Product Dimensions  | 23.88 x 23.88 x 37.08 cm; 5.2 kg |
| Size | 1 Count (Pack of 1) |
| Special Features | Adjustable flow control is built into the inlet and outlet of the filter, 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, The sealed filtration pathway allows you to get the full benefits from all 4-stages of filtration |
| Specific uses | Indoor |
| Style | Biomaster Thermo 250 |
| Voltage | 120 Volts |
| Wattage | 165 watts |

## Product Details

- **Brand:** Oase
- **Capacity:** 70 Gallons
- **Power source:** Corded Electric
- **Product dimensions:** 23.9W x 37.1H centimeters

## Images

![OASE Indoor Aquatics Biomaster Thermo 250,Black - Image 1](https://m.media-amazon.com/images/I/61cwtUdJpVL.jpg)
![OASE Indoor Aquatics Biomaster Thermo 250,Black - Image 2](https://m.media-amazon.com/images/I/71C8dDUhNKL.jpg)
![OASE Indoor Aquatics Biomaster Thermo 250,Black - Image 3](https://m.media-amazon.com/images/I/71GhvYmH9yL.jpg)
![OASE Indoor Aquatics Biomaster Thermo 250,Black - Image 4](https://m.media-amazon.com/images/I/71Ie6fgxhHL.jpg)
![OASE Indoor Aquatics Biomaster Thermo 250,Black - Image 5](https://m.media-amazon.com/images/I/71TZbMDKvpL.jpg)

## Questions & Answers

**Q: My unit is constantly purging air. Is there a solve for this issue? I recently bought mine just a week ago.**
A: It is Amazing to me how Oase will not admit they have a problem with their Biomaster line . I have dealt with Douglas Ward ,President at Oase and Factory rep.
Adam Raabe
Aquatics Category Manager (North America)
Both of them will not acknowledge there is a purging issue . If you look at the design of the filter you will find that whether  it is the 250 or all the way up to the 850 they all use the same head unit all that is different is wattage and impeller  . Foot print of the the whole biomasters is also the same except for height of canister . From my own personnel experience Biomaster 250 has no purge issues . Biomaster 350 for me purged from day one when I got it in 2019 .Biomaster 600 purged right from Day 1 and is still purging with new head unit and also larger diameter pre filter pipe with 3 times as many holes
than stock . Also coarser pre filter sponges . If you look on line it looks like Biomaster 850 is even worse . Where I am going with this is that the whole basic design is built around dimensions of a lesser flow filter and there in lies the problem . All the silicone in the world on orings will not help the issue . When I took the impeller from the 350 and put it in the 600 head the purging lessened ,still there but less frequently . What I have found is the problem is cavitation inside the housing and trying to get more flow from the filter with the same basic dimensions is what is the cause . Simple hydraulics . Where the impeller sits inside the head is the same size no matter what biomaster you have ,I know this because I have the 250.the 350 and the 600. When you call oase they will try to tell you that is you put a pre filter sponge on the inlet tube in the tank it will cause a restriction and you will have purging BS!!! I am using a very fine sponge on the inlet tube of my biomaster 250 (it is in a shrimp tank) and I have let it go until that sponge was caked in mud and had NO purging ,even when I shook the sh!t out of the filter. The design of the Biomaster line is made for the 250 and the 250 alone . It's no secret there is an issue with that filter . I have an Ehiem 2217 since the 1970's and Two Fluvals 07 series . I have been in the hobby now for approximately 60 years and I have owned many filters over that time going back to the leather belt drive piston air pumps and the old Supreme hang on back filters ,I know something about filters. Oase knows they have a bad issue but does not know how to fix it without getting rid of the 350 ,600 and 850. To conclude here is a little tip ,get yourself a smart switch ,something like a Kasa . Set it up with a schedule where it switches off at least twice a day for a few minutes and comes back on . What will happen is that it will do a purge when it comes back on that will lessen the frequency of purging throughout the day . What you would be doing is what Fluvals FX built in feature does to purge built up air in filter . Unlike Oase Fluval needs only one on off per 24 hours . Smart switch will not cure problem but will lessen the purge issue considerably .

**Q: hi I’m having trouble with this filter. It’s taking in air and  it’s starting to make weird noises. who can I contact for warranty help? Thank you :)**
A: Hello. We are sorry to hear that you are having an issue with your BioMaster Thermo 350. You may contact our Customer Care Team Monday through Friday between the hours of 8:00AM- 6:00PM ET. Our Team looks forward to assisting you!

**Q: Does the heater have its own power source? In other words is it independent of the filter. I want to be able to hook the heater to a temp controller.**
A: Hi, The built-in heater provides your aquarium with precise and uniform temperature levels with adjustable control. The heater is on a separate power cord from the filter. Hope this helps!

**Q: does this come with activated carbon foam/media?**
A: Hi, I purchased my biomaster thermo 350 1 year ago and has been running flawlessly ever since. Now, with the stock csrbon prefilters I had minimal purging.... So i switched to the blue 45 ppi and it was much better.... Then I purchase the red 30ppi and I guess 3 times is a charm... No more purging except the first 10 minutes after cleaning them... Then I am good to go for 3 weeks roughly and I will notice a slight decrease in flow and a few light purges which I've come to love. It's a simple reminder.... Hey, clean the prefilter. Do not listen to the ' gunk it with vasoline and buy metal hose clamps. I also have a second 350 and a 250 on my 15 gallon set up. My advice is really take your time conecting the hoses. I use clear hose and lily pipes... So I can't adjust the flow... Am going to get some double taps from oase now that they're available. Lastly, when I switched to the red 30 ppi pre's I notice avery dramatic increase in flow... Hopefully, this helps... I was kinda annoyed at even one purge when I first bought it... But, give it time... Carefully going over each connection. I use no lubricants of any type...just water from the tank... And all filtrrs are set up bottom tral blue stock sponge, all folling trays seachem matrix and top tray stock red foam. Only fill the trays about 3/4th with matrix. Don't stuff it in. The trays might sit uneven and cause issues .....anyway, best of luck...

## Customer Reviews

### ⭐⭐⭐⭐⭐ Review
*by S***. on 29 January 2020*

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.

### ⭐⭐⭐⭐⭐ Review
*by G***P on 10 August 2022*

Really good external canister filter. I set this up for my 40 gal planted aquarium. I use two of the trays for bio medium, one for sponge and the last one with purigen. My water is crystal clear. Filter is very quiet. I am going to leave the main filter running for a few months but clean the pre filter every month as the pre filter can be easily taken out without dismantling the whole filter. The built in heater is very accurate. Now my tank has lots of room for aquascaping as before I had a Fluval submersible filter plus a heater. At first I thought I can save some money and get Oase without the heater but I heard fish can get burns bumping into the heater, I decided to get the thermal version and have not regretted it. I watched a lot of videos on different canister filters before buying this. All of Green Aqua's aquariums have this filter. Well built filter. Some day I might change the output to a Lily pipe but for now I use the included accessory to get surface agitation.

### ⭐ Review
*by P***E on 20 July 2025*

I had high hopes for this filter based on Oase’s reputation, but unfortunately, my experience has been very disappointing. After 8 weeks of starting to use the filter it developed a persistent vibration that caused excessive noise. I contacted Oase support. . They were responsive and sent several replacement parts, but the issue was never resolved despite extensive troubleshooting, including: Replacing components as provided by Oase Insulating the cabinet to minimize vibration transfer Switching to silicone tubing to dampen line resonance Repositioning the filter and hoses to reduce mechanical contact Ensuring all mounting points and surfaces were level and stable Despite all of this, the vibration persists, making the filter unsuitable for a quiet environment like a living room or office.

## Frequently Bought Together

- OASE Indoor Aquatics Biomaster Thermo 250,Black
- FZONE Aquatic Glass Lily Pipe Set with Skimmer Inflow and Outflow for Aquarium Filter 5/8''(16/22mm) Tubing
- Seachem Matrix, 4 L / 1 gal.

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.dk/products/327911721-oase-indoor-aquatics-biomaster-thermo-250-black](https://www.desertcart.dk/products/327911721-oase-indoor-aquatics-biomaster-thermo-250-black)

---

*Product available on Desertcart Denmark*
*Store origin: DK*
*Last updated: 2026-01-24*