Seen it cheaper online? Email us for a deal!

Fluval Q.5 Air Pump Repair Module/Diaphragm (A18831)


1 in stock

Replacement diaphragm for the Fluval Q.5 Air Pump.

To maintin optimum performance of your Fluval Q Series air pump, regular replacement of the wearable parts, i.e. the diaphragm, is required.

Back pressure is the build-up of pressure on the diaphragm due to restricted air flow. This occurs when excess air is produced by the air pump, or when the air channels are inadvertently blocked. Back pressure over time resulting from clogged air stones or other air system blockages and restrictions will cause the diaphragm to expand or rupture. An expanded diaphragm leads to a loss of air volume while a rupture results in the total loss of air.

Air Pump Maintenance:

• Airlines should be carefully inspected whenever standard aquarium maintenance is performed. Adjust, or if required, replace all sections which are pinched, kinked, or otherwise damaged.

• All attached air-driven aquarium ornaments should be regularly maintained. Algae growths should be
removed from moving parts and kept as clean as possible. Internal air tubes should be cleaned.

• Air stones should be kept clean and free of debris or algae build-up. The ideal situation is to replace them every month, alternating with an extra set which has been dried over that period and cleaned before being placed in the aquarium.

Two complete sets of air stones alternately changed each month will extend the life of the air stones and help keep back pressure to a minimum. Clogged air stones and air-driven aquarium ornaments will lead to low air pressure output and also reduce the life of the diaphragms.


If the air pump fails to produce air, check the following:
1. Ensure that the air pump is plugged in.
2. Ensure that there are no blockages in the air hose assembly and that all valves allow air passage. If no air is produced by the accessories in the aquarium, remove the air line from the pump and ensure that air is being produced.
3. If the air pump produces no output, the most common problem encountered with any air pump is a ripped or weakened diaphragm. Remove airline. Unplug appliance. Inspect the diaphragm for tears or rips. Any opening in the diaphragm will make it impossible for the pump to produce air for aeration purposes.

Always inspect the diaphragm first before replacing other parts in the pump.


Repair modules for all wearable parts are available for all Fluval Q series air pumps.

A18331 - Repair Module for Fluval Q.5 Air Pump
A18332 - Repair Module for Fluval Q1 / Q2 Air Pumps