Aeration Essentials

In this warm weather, you need to ensure that your fish are looked after and have enough oxygen to breath.

A common question we get is asked is 'I have a waterfall and/or venturi, surely that's enough oxygen for my fish?'

Not entirely. Waterfalls and Venturis do provide some oxygen in the pond but as the oxygen bubbles enter the water they are very close to the surface of the pond so they gas off the surface of the pond very quickly without full saturation into the water. Waterfalls and Venturis should be used in conjunction with an air pump and airstones. The airstones can be placed lower into the water to the bottom of the pond, so as each oxygen bubble takes longer to arrive at the surface of the pond more oxygen is delivered in to the pond water, increasing the oxygen available to the fish.

The warmer the pond water, the more oxygen you need to add to the pond.

Oxygen is depleted faster in warm water than in cooler water. So in Winter there is less of a need to add extra oxygen than in the warmer Spring, Summer and Autumn months. Using a dedicated air pump to pump more 
oxygen into your pond during these warmer months is a must to maintain a good healthy pond and healthy fish full of vitality.

Some possible signs that you might need to add more aeration to your pond water 

  • The Koi and pond fish are spending alot of time on the surface in the bubbles of your waterfall or fountain
  • The Koi and pond fish are gasping at the surface
  • The Koi and pond fish are moving very slowly in the water and may not be eating as much food.

What options are there?

Simple pond setups need only an air pump, airline, manifold and airstones. 

Things to think about when choosing the correct air pump:

  • How deep is your pond! The deeper the airstone is going to be in your pond, the more water pressure there is around the airstone, so the more powerful the air pump will have to be to push the air down to the airstone.
  • Aeration causes turbulence on the surface of the pond! If the pond surface is quiet small and a large air pump is used then it may become difficult to see your fish through the large amount of air bubbles created by the large pump. For ponds that have a small water volume and are shallow, then air pumps like the Hailea V-10 and V-20 are ideal. For ponds with a larger volume and deeper then pumps like the Hailea 9730 and Enviro ET Series Pumps (almost identical to the HAP series) - ET80, ET100 & ET120 are best suited.
  • Would you prefer to use rubber air diffusers or ceramic stones? There are many choices of air diffuser available and some are best suited for use with certain air pumps and pond setups. 


We have a large range of pumps, airstones & discs and all other air accessories in stock today. Not to mention a limited amount of Aquarium aeration products for growing on or quarantine tanks.

With this in mind if you would like any advice on the above, then please do not hesitate to come and see us instore or contact us on We will be happy to help talk through your pond aeration requirements and ensure you have the correct equipment for your pond and fish.

18th July 2014

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