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).
To lower the pH of 100 ml of water to a pH of 5.5, it would take only around a drop of lemon juice. It is estimated that in a gallon aquarium, two drops of lemon juice can lower the pH by .5.
Most likely you have high Nitrates, which will lower your pH, or you just changed water, and used water that you don't usually use, or you added something that changed it.
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You will need to test the PH, KH & GH to find out whether your water is soft or hard. If your PH changes easily in the tank, then you can add crushed coral to help it rise and be stable, or peat moss to help it lower and be stable
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The pH is unchanged.
No it cannot. Sodium bicarb has a ph of 8.4. To lower ph you would need to use a dry acid (sodium bisulphate) or muriatic acid. City water is normally treated and has a ph of 7.5 but it would take a large amount of fresh water to lower the ph of a pool.
No you add acid to lower the pH
Adding 20 mL fresh pure water to fresh pure water: the pH remain unchanged.
There are a variety of elements in all water. Each element carries with it a specific PH. Salt water maintains PH ranges anywhere from 8.4 to 7.6. Fresh water carries different elements and the PH range can become lower, down to as low as 6.0.
The pH become lower.