Also I have another question. Ive been using my ta...

A lot depends on the type of humidifier. If it's a steam type the minerals will be left behind in the dehumidifier as the steam is mostly pure water vapor. If you have a cool mist type all those minerals get blown into the air. When the water evaporates the minerals fall like microscopic snow. Eventually you might notice a white film of minerals develop. How do you know the mineral content of your water? pH is not a great indicator. Many municipal water systems treat the water specifically to raise the pH so you can have a high pH without having a crazy high mineral content. Still, there will be minerals in the water.