The pH scale is used to measure how acidic, alkaline or neutral your water is. The scale ranges from zero (most acidic) to 14 (most alkaline), with 7 being neutral. Most freshwater fish survive in a pH range of 6.4 to 7.8. PH can be tested for by using a standard water test kit. However, testing your water directly from the tap will not always give you a true pH reading.
Time Will Tell
Tap water in your water lines lacks oxygen. The exchange of oxygen and carbon dioxide are important factors in generating a proper pH level. As the water oxygenates, bubbles carry carbon dioxide to the surface. These bubbles release the carbon dioxide into the air, removing it from the water. This exchange of gases will cause your carbon dioxide levels in your water to lower, which will make your pH rise. This process usually takes 24 to 48 hours.
Chemicals Play a Role
Most of us get our water from a municipal source. This water contains chemicals that are added into the water for conditioning. As stated on the website of the National Health and Medical Research Council, chemicals are added to the municipal water supply to control algae growth, reduce organic matter, remove microorganisms and to control odour and taste, just to name a few. These chemicals will alter the parameters of your tap water. Using a dechlorinator will help to eliminate these chemicals.
Impact of Low pH
PH impacts a variety of parameters in your tank. If your pH drops below the 6.4 mark, you run the risk of having the beneficial bacteria in your tank die off. This effect can cause your tank to crash, killing your fish in the process. There are a number of pH buffers available on the market to help combat this problem. These buffers should be added to your tap water prior to being added to your tank. Your local fish store should have a good selection available to you.
Test Your Test Kit
Inaccurate readings from older water test kits are common. You should replace your test kit every six months. The chemicals used in these kits will eventually have a chemical reaction to the bottles they are in, and your test kit will provide false readings. Not following the instructions contained in the test kit will also lead to false readings. If you are unable to purchase or use a water test kit, you can take a sample of your tap water to your local fish store. They will be able to test it for you.
Maintain a Stable PH
Most fish adapt quickly to their environment. It is more important that you achieve a consistent pH then a specific pH. Huge and sudden changes in your pH can be very dangerous to your fish. When using tap water, find a pH that works for your tank, and stick to it. Using tap water in your tank will take a little time to perfect, but in the end it will provide a cheaper and easier alternative.