My son has been redoing my bathroom for 4 weeks. He told me it was ready for me to use the tub, but when I tried it the tub leaked water downstairs. I suspect the drain in the bottom of the tub hasn't been installed properly, but he threw the instructions away. Can you help me? I tried putting water into a bucket to see if water leaked from the wall, it didn't. It only leaks when water is in the tub itself. I only have one bathroom in my house and am anxiously looking forward to solving this problem.