Hi, just installed. The pump is very (very) noisy. Is there something wrong with my pump or am I missing something as you can only plug it in.

Mine is really quiet, it only vibrates loudly if touching anything accidentally. You'd probably need to send it back, otherwise it's a great air pump and does the job

Is the strength of the pump adjustable?

The output strength (the amount of bubbles) is adjustable via a valve

Can this be used in a large fish bowl and would it be ok for betta fish?

this pump is for tanks 10 to 60 litres for tanks 50 to 100 litres http://www.amazon.co.uk/Tetra-T282-APS100-Air-Pump/dp/B000S5JMVU/ref=sr_1_fkmr0_1?s=pet-supplies&ie=UTF8&qid=1447591969&sr=1-1-fkmr0&keywords=extra+aps if your not sure how many litres your tank is heres a link to a calculator http://www.ifocas.org/calculator.htm hope this helps

could i use this pump for a sponge filter?

I'm not up on EVERY kind of sponge filter but mine is powered by an air pump. It's made to be. If you have the kind with a cylindrical spunge, wrapped round a plastic moulded core, which has an air line attachment, then 'yes'. Some have a single sponge and weighted base. Some have 2 sponges and a sucker mount. The flow of bubbles up a column within the core of the sponge effectively creates a vacuum effect that sucks the flow of water through the sponge. With those kinds of sponge filters, that have fittings for attaching an airline, you need an air pump to power them. They're cheap but source an appropriately powered/ sized pump according to the volume of water you have in your tank. Pump makers supply this info in listings or on boxes, usually in litres, to help you with choosing the right one.

Pet Type	Fish and Aquatic^Fish and Aquatic
Product Dimensions	11 x 11 x 11 cm; 200 g
Item model number	T281
Colour	Black
Size	10 - 60 Litre
Number of Items	1
Quantity	1
Compatible Devices	This pump is perfect for a variety of aquarium needs for tanks 10 to 60 litres
Special features	Tetra Aquarium Air Pump is perfect for adding extra oxygen to your fish tank, running filters and air stones.Special vibration-absorbing rubber feet
Specific Uses	Indoor^Indoor
Batteries required	No
Batteries Included	No
Item Weight	200 g

Tetra APS50 Silent Aquarium Air Pump for Fish Tanks,Black,10 - 60 Litre

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Common Questions