The floatation unit technology is considered a more advanced methodology than the sedimentation approach as it is more effective in separating most contaminators regardless of its size no matter how small and tiny it was and irrespective of the minimal density difference between the water and most contaminators. The sedimentation approach depends on using assisting water that contains more dissolved air than the normal water under the regular conditions and therefore, once the over saturated water (assisting water) enters the container of the floatation unit filled with contaminated water, small bubbles will formulate immediately sticking most of the contaminators that exist in the contaminated water, whether small of big leading to a reduction of its density and thereof floating on surface during a short period of time. The floating sludge can be removed mechanically.