What else could be wrong with my water heater
I have a RUUD Water heater, approx 8 years old. Recently, the hot water started lasting less and less time. Last week, I replaced both elements and both thermostats. I flushed the heater and an ordinary amount of sediment came out. I filled the tank, put the electrical back on, and after a couple hours it seemed to be working fine again. Now, I'm getting the same problem, the hot water lasts one shower and then its warm and not so warm thereafter. What else could it be? I retested both elements for continuity, they are good.