Hello Roundtable Friends......I need some advice on my hot water tank/water pipes. For some time now (months) my pipes have been making a loud knocking sound when water is turned on anywhere in the house. Sometimes it sounds like they are going to burst. Now my hot water tank is making gurgling sounds also, even when no one is running water. Any suggestions on what is causing this? My husband is pretty handy at a lot of things, but he's stumped on this one. My initial thought was to call a plumber, but I want to make sure that they know what they're doing....as I've had some real doozies before. Thanks for your input!