Aquarium help > New tank syndrome & NH3 > why does NH3 go up when I do water changes?
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    Free ammonia NH3 can go up when you do water changes if the new water has has a higher pH.
    NH3 and NH4 always form equilibrium with pH and temperature. When you do a water change the new water will often be harder and have a higher pH than the water you are removing. This is because organic acids from fish / plant waste and other biological activity will remove the waters hardness and lower the pH. On changing water a move to a higher pH will unlock NH4 into NH3 and the transition can happen in fractions of a second.
    If this is the case for you then keep repeating 20% water changes and eventually the NH3 / NH4 will start to reduce through dilution.
    A seneye device will report this change in pH, temperature and free ammonia.

    TIP: You can use your seneye to check the water you are using for a water change. It will allow you understand how much pH difference there is between the water you are about to add and the tank water. 


    To understand more visit this link on NH3/NH4.

    To understand ways to better reduce NH3 please click here..