Video

Excellent! You are the only one that addresses the primary problem. All of the other videos on CZcams say to lower the water level. This toilet was designed to have the water level higher in the tank for the best flushing using gravity. Many tanks have a fill line marked on the inside of the tank indicating the correct level. Lowering the water to half of the tank level reduces flushing efficiency. The flapper needs to close more quickly. There are three ways to make the flapper close more quickly. The most common problem is that the overflow tube in the center of the toilet is filling too quickly with water from the little tube from the fill valve. In the USA, on many Korky fill valves (the thing usually on the left of the toilet), there is a flow adjuster to regulate the flow. Turn this down to decrease the flow going into the overflow tube. You can confirm if too rapid flow is a problem even without an adjuster valve by turning down the flow at the valve adjacent to the wall and seeing if the flapper closes quicker. If that doesn't work, try one of the adjustable flappers by Korky or Fluidmaster. If all that fails, add a brass nut or a washer or two or three feeding it over the chain so that it rests on the flapper.