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Forgive me if this has already been asked but I didn't find anything in the search. I did a test of my water today and while the pH is a little low, the strip is telling me the water is very hard. I have stuff to adjust the pH and I have the stuff that takes out chlorine, but I don't know if that is the stuff I need to use to adjust total hardness. Or if I even need to do anything. How does the hardness affect the system and what should I do?

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I'm not very trusting of test strips.

If your pH is between 6.5 and 8.0 (you need to leave the water air out for a day before trusting the pH of the water from the tap, water directly out of the pipes will have a false low pH reading because of dissolved carbon dioxide acting as a mild acid, once that outgasses the pH will probably be higher than you thought) you should be good, if the pH of your aired out water is above 7.9 or so it might be worth bringing it down a little before you start cycling but it will generally come down naturally on it's own. 


As far as the hardness, it is likely to sort itself out in time too and you will eventually probably need to add something to bring it back up once your system is mature.

Hi Windy,

Here is info I have on file about water hardness that I use.


Temporary Hardness
Some agents which contribute to hardness can be removed through reactions within the aquarium environment. Dissolved carbonates are often the cause. This carbonate hardness (KH) acts as a buffer on the water pH. As long as there is dissolved carbonate above 3 degrees of KH the pH will be stabilised in the alkaline range.

Permanent Hardness
Even more important for fish is the permanent hardness value. This is usually linked to the calcium and magnesium levels within the water. It is also known as general hardness (GH).

This is the more important form of hardness because it is not fluctuating with any pH changes. When measuring and adjusting it should be permanent hardness that is concentrated on.


Adjusting Water Hardness
It is a lot easier to increase hardness than it is to reduce it. For this reason it can simplify matters if you choose fish suited to your local water conditions.


Manufacturing your own soft water can be done using a reverse osmosis filter but these are prohibitively expensive  Devices that remove hardness using ionic exchange can also be obtained.


Where practical, soft water fish are best kept in adjusted rainwater. This will not be possible in areas of significant air pollution however. Filtering tap water through peat should be used in such cases. Box filters can be packed with the dry material and the hardness will be removed as it passes through the filter. Demineralised water can also be used if required.


Increasing hardness can be achieved by using water hardness products such as calcium carbonate, magnesium sulphate or calcium sulphate powders. When administering these products they may not immediately dissolve. A white sediment may settle on plants and ornaments but this will dissipate over a few days. Some clouding may also be experienced from the suspension of fine particles.


Hope this helps.

It does! Thank you!

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