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Oase Living Water BioMaster Thermo 250

Code: 42745
  • £219.99
  • ( )
  • RRP £229.99
Item in Stock   |   Usually dispatched within 24 hours

Oase BioMaster Thermo 250 external filter for tanks up to two hundred and fifty litres. Made from high-quality materials the Bio Master is robust and also has a very modern look. Designed to provide mechanical, biological and also chemical filtration if you wish. External filters are in general much the same but the Oase Bio Master Thermo 250 differs slightly. The Bio Master comes equipped with an easy to clean pre-filter that can be cleaned without opening the filter. The pre-filter consists of high-grade foams that trap most of the debris.  The idea is that the debris removed by the pre-filter extends the service interval of the main filter.

The Oase BioMaster Thermo 250 main filter.

The filter's main section features two foam filter stages prior to the Hel-X media filled bio’ stage.  Hel-X 13, specially designed for use within the Oase Profi Clear Premium Moving Bed Module and Oase Profi Clear Premium Compact range of Drum Filter systems. So I would swap that out for a much better media, such as Seachem Matrix  Or Eheim Substrat Pro. Pretty standard view in the trade and hobby.


Pre-filter we have already covered. The best bit in a word, handle, great job Oase all filters should have a carry handle makes life so much better. Auto shut off and lock, which prevents water loss when the pre-filter is removed. A built-in primer for easy priming and startup. The all-in-one shut off valve, is also used for flow control. Easy service for the main filter, simply slide off the all in one valve block and release lever unclip the catches and clean.

Built-in heater.

The Oase Bio Master Thermo 250 is just the 250 Biomaster with an Oase HeatUp 150 Watt Heater fitted. In the head of the normal 250 there is a gland that allows you to add a heater, the thermo comes with the heater fitted.

External Filter Specification
Suitable for aquariums up to max. 250 l
Dimensions (L x W x H) 240 x 240 x 370 mm
Rated Voltage 230 V /50Hz
Power Consumption filter + heater 15 + 150
Net Weight 5.20 Kg
Guarantee (+ request guarantee) 3 + 1
Max. Flow Rate 900
Max. Head Height 1.30 m
Hose (quantity/length) 1Unit/4m
Connection for Hoses ø (inner/outer) 16 / 22
Filter Volume 4.4
Pre-filter Volume 0.40
Suitable for Freshwater Yes
Suitable for Saltwater Yes
Contact us with any questions you have about this product

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Orders after that time will be processed the next working day


Please Note: We only deliver ponds and pond plants on our own delivery vehicles!

The blue highlighted area on the map below is where we deliver on our own vehicle! Unfortunately, if you are not in one of these postcode zones we are unable to deliver certain items such as plants, small glass items and selective other products.



We offer a few different delivery options depending on the size and value of your order.

Orders over £50 qualify for free mainland UK (excludes Northern Ireland) delivery which will arrive within 3-5 working days of the order being processed.


Residents of Northern Ireland, please provide your EORI or XI Number.

If you do not have one, please follow the information at


Orders Below £50 in Mainland UK will be charged a standard delivery fee of £5.99.

Additional Shipping Charges

For any orders that do not include Aquariums, the below is charged:

Next Working Day Parcel Delivery to Mainland UK - £7.99 OR £2.99 if the order is over £50

Standard Parcel Delivery to Northern Ireland £8.99

Standard Parcel Delivery to Scottish Highlands & Islands £9.99

Standard Parcel Delivery to Jersey & Guernsey £12.99


For all Aquarium deliveries (Excluding biOrbs & Smaller Aquariums), the below is charged:

Next Working Day Pallet Delivery - £20

2 Hour Booking Slot Pallet Delivery - £20

Pallet Delivery to Northern Ireland - £45

Pallet Delivery to Isle of Wight (PO36 and Above) and Scottish Highlands (AB, PH, IV1-36, IV, KW1-14, KY, PA21-41) - £45

Pallet Delivery to the Scottish Isles (KA27-28, PA60-90, ZE, JE, GY, IM, IV40-56, KW15-17, PH42-44, PA20, PA42-49) - £120

Pallet Delivery to Outer Hebrides (HS) - £140