The Weald Aquatics Blog - Oxygen in Ponds - another blog post from Weald Aquatics | Aquarium & Pond Fish Shop in Kent


Coolings Green & Pleasant
Main Road, Knockholt, Kent TN14 7LJ

01959 532 963

Opening times

Monday to Saturday
and Public Holidays: 09:00 - 16:00
Sunday: 10:00 - 16:00

As a pet shop, we are exempt from the government's ban on shop closures. So we cautiously welcome you if you need any supplies during this time. However, whilst in the shop please observe the rules on social distancing in order to keep yourselves, other people and our team safe and well.
Site Menu

Oxygen in Ponds

Blog post written by Gary | 24 May 2016 | Category: Pond maintenance

Keeping a good level of oxygen saturation in the pond in the summer months will improve your pond water quality and keep your fish healthy.

Oxygen levels will deplete at night time in the pond due to photosynthesises not taking place. The algae will take in oxygen and expel carbon dioxide; this can be fatal to oxygen loving fish.

Adding pond oxygenating plants into the pond will add oxygen in daylight due to photosynthesis but can cause problems at night again due to the plants taking in oxygen and releasing carbon dioxide.

Low oxygen levels can also occur in hot, sultry and thundery weather due to the low air pressure. Also, there are lower levels of dissolved oxygen in warmer water.

There are several ways to keep the oxygen level correct for the number of fish you have in the pond. Pumping the pond water through a filter with a UV lamp returning via a waterfall will inject more oxygen into the water and at the same time eliminate greenwater which will cause low oxygen levels at night.

Having a pump with a fountain unit fitted will also oxygenate the pond water helping the fish and water quality but will not eliminate green water algae.

Fitting an air pump to the pond is the most effective way to get more dissolved oxygen into the pond. Air pumps have a number of air stones which can be placed in different parts of the pond giving water movement and forcing more dissolved oxygen into the water.

Having more dissolved oxygen in the pond water will not only keep the fish in good condition, it will also help to break down the organic waste in the pond which will help keep the algae levels to a minimum.


Pond air
Air pumps