1. The safest solution is to replace the fitting pipe at the leaking location. Close the main valve, drain the water, use ppr scissors to cut off the leaking part of the pipeline, use the PPR hot soup machine, add a section directly. The process is not complicated, and a skilled worker can solve it in 30 minutes.
2. Wipe dry the leaking parts and buy a good one with plugging king (waterproof cement). Add a little less water if it is very thick, just leave it at the leaking place under the batter. This method is often used to remedy cast iron drain pipes.
3. Use polyurethane waterproof powder (usually used in bathroom waterproofing) to adjust the water and paint on the leaking place.
4. Use weathering glue to hit the leaking place