VIVO_1-2013-en

0°C 32°F 0 2 4 6 8 10 12 14 16 14,64 12,81 11,35 10,18 9,19 8,37 7,67 5°C 41°F 10°C 50°F 15°C 59°F 20°C 68°F 25°C 77°F 30°C 86°F 11 VIVO How does oxygen get into the water? Plants produce oxygen during photosynthesis – another reason to use plants in a pond! Fast growing submerged plants release particularly much oxygen into the water and thus strongly contribute to a healthy pond climate. It may at least in large ponds be possible to separate a part inaccessible for the fish and cultivate the plants there. This prevents the fish from consider- ing them a welcome vegetable food and eating them. An entirely sufficient amount of oxygen gets into the pond water via the water surface. It is advanta- geous to provide the pond with a brook. The flowing water takes up additional oxygen, furthermore the sur- face becomes larger due to the formation of waves. This surface agitation is at the same time an effective measure against the formation of oily layers that inhibit oxygen uptake. Reasonable water circulation by a filter pump is important for distributing the oxygen evenly. Ponds are subject to seasonally and climatically caused temperature variations. Accordingly, the oxy- gen level varies strongly. Like all gases, oxygen dis- solves better in cold than in warm water. More than 14 mg/l are dissolved at 0°C (32°F) and 100% oxygen saturation. At 20°C (68°F) it is approximately 9 mg/l, at 25°C (77°F) only about 8 mg/l. Depending on the or- ganic pollution, 100% saturation are often not achieved – and 50% oxygen saturation at 25°C (77°C) then only represent approximately 4 mg/l! Measuring the oxygen level It is therefore recommended to check the oxygen level regularly. 4 mg/l are considered a minimum level for keeping fish. However, higher oxygen levels are advisable and create some sa- fety margin, especially during summer. The sera oxygen-Test makes it easy to check the oxygen level of the water within minutes. In case of insuf- ficient oxygen it is important to find out about the causes immediately and to remove them. In case of acute oxygen deficiency it is ad- visable to add sera O2 plus for immediately impro- ving the oxygen supply. The powder is simply sprinkled onto the surface. sera O2 plus combines immediate and long term oxygen supply. Temperature dependency of the oxygen level (always 100% saturation) mg/l O2 Flowing water of a brook takes up additional oxygen. ©CindyHaggerty–fotolia.com

VIVO_1-2013-en

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