My coolant light comes on after driving about an hour, its not overheating

What is your question?

I have to add coolant before I drive the car every time. Its not pouring out the bottom or out of the cap. Ive replaced the thermostat about 3 times. its using coolant while driving the car. the temp stays under the half mark. its not overheating. when I go somewhere, I have to stay a while for it to cool off, then add coolant before I leave or the light will come on while driving. please help