You may notice that the pump becomes noisier or the bubbles less vigorous. At which point it may be time to replace your air pump. Replacing the air pump is simply a case of unplugging the old one and plugging in the new. Simple instructions are supplied. If your air pump stops working replace it as soon as you can to minimise interruption to the filtration. It is advisable to keep a spare air pump so that if it fails you can replace it straight away. If the bubbles have stopped it may not be the air pump, check our help pages for more information. Suitable for all sizes of biOrb & biUbe aquariums.