Does the temperature of my pond water effect the oxygen supply?

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Does the

temperature

of my pond

water

effect the

oxygen supply?

The temperature of your pond water has a profound effect on the amount of dissolved oxygen available in the pond. The hotter the water the less oxygen it can hold, therefore cold water holds much more oxygen. Using a small bubbler, air pump or aerator adds enough oxygen for most size ponds in the winter. Most pond fish do not require a lot of oxygen in the winter because of hibernation.

Warm water has a low capacity for holding oxygen

while cooler water can hold gigantic amounts of oxygen. Warm water and increased activity go hand and hand, and that increased activity means fish like Koi require more oxygen. Oxygen dissolves in water at very low concentrations. Our atmosphere is about 20% oxygen or 200,000 ppm but seldom will a pond have more than 10 ppm oxygen dissolved in it’s water. Dissolved oxygen concentrations below 3 ppm stress most warm water species of fish and concentrations below 2 ppm will kill some species. Often fish that have been stressed by dissolved oxygen concentrations in the range of 2 or 3 ppm will become susceptible to disease. The recommended minimum DO Requirement range 6.9 mg/l – 9.1 mg/l. Although it is expensive many purchase Do readers. It is not necessary, if you just watch your fish you can tell if they have enough oxygen. They will swim around happily and eat normally.

Oxygen dissolves into water from two sources: the atmosphere and from pond plants in the water. The primary source of oxygen for a pond is from microscopic algae (phytoplankton) or aquatic pond plants. In the presence of sunlight, these produce oxygen through photosynthesis and release this oxygen into the pond water. At night and on very cloudy days, algae and submerged plants remove oxygen from the water for respiration. During daylight hours plants normally produce more oxygen than they consume, thus providing oxygen for the fish and other organisms in the pond Without oxygen, filter bacteria cannot oxidise (and detoxify) ammonia into nitrite and then into nitrate. If a pond or filter are allowed to become oxygen deficient for any period of time, anaerobic conditions will prevail causing unstable water conditions and the tell-tale bad-egg smell.