The way I did it was I opened the drain plug and let as much possible come out. Closed the plug and filled the raditor with water. Warmmed the car up again. Then drain as before, and refilled with water. I repeated that for about 6 times until the water coming out was pretty close to clear. Then I added the water wetter and plain water.
But if you say that by removing the bottom hose, all the water (Including the fluid in the engine) comes out, then this is the way to go.