I've been dealing with a slow draining sink for some time now. I broke down and bought some FlowEasy Drain Opener. It said to let the sink fill with cold water and then slowly pour the cleaner down the drain and let it sit for 15 minutes. The problem is every time I poured a little cleaner in the drain all the water would run out. When I turned the water back on it would just build back up in the sink again and this process went on 4 or 5 times. What do I need to do to fix this problem? Any help will be greatly appreciated.