Learn more of the importance of oxygen and air in ponds especially fish ponds

This is a 250 word (approx) summary of a chapter from my water gardens book. For a complete list of summaries see the right hand column

Concepts: oxygen/air, pond, water, air, plants, temperatures, waterfall, filter, Peter Waddington, fish, oxygen concentrations, carbonate, high levels, saturation level, mg/litre.

Summary:

- If I learned nothing else during all those seminars I attended with Peter as my guest it was that you cannot overdo the addition of oxygen/air.

- Peter's own pond and filter literally bubble with air which is continuously pumped into the circulating water, the filter and the waterfall as well as the pond 24 hours a day 365 days a year.

- By the way my pond does not have any additional sources of oxygen than a waterfall and a second water flow into the pond from the biofilter.

- If I doubled the fish mass I would probably need to introduce more oxygen into the pond.

- This is why trout need cold water - they need high levels of oxygen that they cannot get in warm water.

- At 20 deg C it can only hold 8.8 mg/litre and at 30 deg C the saturation level is 7.5 mg/litre.

- In practice very few systems reach these saturation levels and this is the reason Peter Waddington blows massive amounts of air into his pond and filter in order to get as close as possible to saturation.

- Plants are always a good idea in a pond because they introduce oxygen into the water during the warmer parts of the 24 hour daily photosynthesis cycle.

- The higher temperatures occur during the day when oxygen concentrations would tend to be at their lowest due to higher temperatures.

- At night however the plants reverse this process by using up oxygen from the water and converting it to carbon dioxide and then to carbonic acid.