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Care of Fish
Freshwater Aquariums

How do you lower the pH of a fresh water aquarium?


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Wiki User
July 12, 2009 9:20PM

This is quite difficult to do because water contains its own 'buffering' chemicals and will try to return to its normal pH value. There is also the problem of inballance when performing water changes (which should be done regularly).When this happens the occupants ofthe aquarium can easily be damaged by the pH fluctuations. "pH down" that usually comes with pH testing kits is absolutely useless and will cause those dangerous fluctuations. That having been said, there are other products available at most pet shops. These products are added to the filter and they remove some of the buffering capabilities in the water thereby dropping the pH slowly and gently. Peat moss is another but more natural item that can be added to the filter and it too will lower pH levels slowly by adding tannic acid. It will also change the colour of the water making it brownish (tea coloured).