Due to their vibratory design the chances are that at some point you've had to deal with a noisy air pump. This is exceptionally common, but here are the answers to some of the questions you might be asking yourself when dealing with noisy air pumps for aquariums.

How do air pumps work?

Air pumps work using an electric coil which sits opposite a magnet on the end of a metal arm. The back of the metal arm is screwed to the top of a rubber diaphragm. When plugged into the mains, the alternating electrical current causes the magnet to flip from side to side, moving the bar with it and vibrating as it goes. This makes the rubber diaphragm pump move in and out very quickly, which sends a flow of air to an outlet to which you can attach a special narrow hose called an airline.

The air pump forces the air along an intake pipe into your tank, where it is released in the form of bubbles. Air stones or diffusers are used to reduce the size of the bubbles produced. As the bubbles travel to the surface they agitate the water, which boosts gaseous exchange and drives off potentially toxic carbon dioxide which is produced by aquatic plants and respiring creatures. It is worth noting that air stones are disposable and can not be cleaned, because they suck in dirt from the water which blocks the tiny pores in their structure.

The air pump itself isn't waterproof and needs to be placed below the aquarium in a spot well away from water. Since they're naturally vibratory by nature, some noise is inevitable, but keeping it inside your aquarium cabinet can help muffle the sound if you have a quiet room or very good hearing.

Why do I have a noisy air pump?

The most probable cause of a noisy air pump is a worn diaphragm. After rapidly pumping up and down millions of times a day, the soft rubber of the diaphragm will eventually start to perish and crack, and it's at this point when the air pump starts to become noisier.

Diaphragms are disposable items and need to be replaced every year or so to keep the air pump operating quietly and efficiently. Since they're wear and tear items, they're not covered by the warranty and you're expected to replace them, just as you would the tyres on your car.

Other reasons include that you are forcing the air pump to work harder by making it pump air into a deeper tank, which offers more pressure and resistance, or gradual movement of the diaphragm which causes increased vibration in the pump.

Nine times out of ten, there's no need to go through the hassle of returning your air pump if it's started to become noisy. It's generally pretty easy to fix with a bit of a basic maintenance, starting with the replacement of the diaphragm and flappers, if it has them.

Do air pumps have noise ratings?

Although air pumps do include noise ratings they are not often published with the products are they can be very confusing and vary between manufacturers. These days, most air pumps are fairly quiet and only really become noisy when they're in need of maintenance or are being placed under too much stress, perhaps by dirty airstones or restricted airlines.

What maintenance do air pumps need?

Aquarium air pump maintenance will usually come down to the diaphragm used to pump the air. Because the diaphragm is constantly moving it will eventually wear out, or simply slip out of position.

Just like the tyres on a car they will need eventually need maintenance to perform at their best. Some models also include a tiny flapper valve inside which may require replacement. Both bits are available, along with the tools to do the job, in a handy kit, which is specific to the air pump model you're using.

Is it worth getting an air pump repair kit?

We would always recommend getting your hands on an air pump repair kit or air pump maintenance kit. These kits usually include the replacement membrane and tools required to remove the old membrane without damaging the pump.

There is really very little that can go wrong with these pumps other than the eventual wearing out of the diaphragm, which can easily be replaced with one of these maintenance kits.

Each manufacturer will offer their own kit for their individual brand. For example, the Biorb Repair Kit would contain a replacement diaphragm and all of the required tools specifically for use with a Biorb Air Pump. You can order these from us for most of the popular air pump models.

How can I avoid a noisy air pump?

If you are finding that your air pump is getting on the noisy side then a good piece of advice comes from Aquamedic technical advisor Ted Heaton, who states that "you buy cheap, you buy twice", meaning that it's always a good idea to invest in high quality products and to maintain them.

This is where the air pump maintenance kits become so invaluable as they will allow you to replace worn out parts like the pump diaphragm, without needing to spend money on an entirely new product. Make sure you regularly replace your airstones, as they become clogged with debris, and this can place the diaphragm under pressure which makes the pump noisier.

Does placement affect a noisy air pump?

Placement of your air source pumps can greatly affect the amount of noise it makes. According to industry experts there a number of cheaper ways to go minimise the amounts of noise produced by your air pump, in addition to regular maintenance of the membrane.

These include suspending the noisy air pump at, or above water level to reduce the resistance of water on the air pump and regularly maintaining the moving parts within the noisy air pump.

It is very important for your own safety and the safety of others that the air pump is not positioned so it could either fall in the water or get splashed. Air pumps are not designed for exposure to water, and touching a wet air pump could result in an electric shock.

Basic tricks to reduce the affect of a noisy air pump include keeping the air line length to a minimum and placing the air pump on a vibration-absorbing surface such as foam. It is also advisable to experiment with the placement of the air pump, as some surfaces can amplify the noise produced.

What is a non-return valve and why do I need one?

A non-return valve is an essential air pump accessory that no air pump should be without. In the case of a power cut, if the air pump is below the water level of your aquarium the tank water could begin to flow back through the piping and into the air pump. This is a quick and easy way of breaking your air pump, not to mentioned making it incredibly dangerous.

Is a noisy air pump covered by my guarantee?

All air pumps make noise, however they are much improved in terms of design in the last few years, with most manufacturers doing all they can to minimise noise, such as adding pointed rubber feet to absorb vibration.

With this in mind, your air pump making noise will most likely not be covered by a guarantee since with the aid of a maintenance kit the problem can most likely be fixed by replacing the worn out, or displaced diaphragm. In general, most noisy air pumps can be fixed through proper maintenance, but all are, by their very nature, a little buzzy...

What size air pump do I need?

When it comes to air pumps bigger is always better. As a rule of thumb it is always better to get a larger pump as you can always bleed off any of the excess air that is not required while still having a pump that is powerful enough for any larger aquarium tank that you may get in the future.