... This air pump and all of Rena's air pumps can be used for either tropical fish of cold water fish.
Although fish don't actually breath oxygen from the air, they do need the oxygen that is dissolved in the water. They make use of this oxygen by gills, which is the equivalent to our lungs.
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"...is smaller than this then Rena do make smaller air pumps:
Rena air 50 for 5 - 30 litres
Rena air 100 for 30 - 90 litres
Rena air 200 for 80 - 160 litres
Rena air 300 for 120 - 300 litres
Depending on what air pump you choose and need will vary on the amount of oxygen will be pumped into the aquarium. The Rena 400 has two air outlets which is great as it means you get twice the output, which is 400 litres of oxygen every hour.
As this is ..."
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