On your show you mentioned fixing a valve to solve the problem of slow water. Can you clarify which valve it is? And is this a DIY project? I am handy, but not so handly that I want to handle a propane torch. My house is about 50 years old, if that matters. Any help is appreciated!
It sounds like there's an issue with a valve supplying hot water to your tub and your sink. The valve may be partially closed or obstructed. You're going to need to hire a plumber to take apart the valve in the tub and check the pressure. Often debris gets in pipes, and even small pieces can clog a valve up. Since you have an older house, you also want to consider - while you have a plumber there - replacing your existing shower valve with a pressure-balanced valve. Pressure-balanced valves maintain the mix of hot and cold water, so you'll get the temperature you want regardless of water pressure. No more spurts of hot or cold!