Don’t forget the toilet flappers if you have them. A super small leak adds up over time

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^ ^ ^ this
I just replaced one that was leaking somehow, and would
flush the toilet on it's own. I've had em go bad and dribble,
but never one like this one. A little spooky when that happens
during the wee hours.
Cheap and easy repair

Have a 60 gallon electric water heater. It was new in 2006. In 2013 it quit heating and I had to drain and replace the heating elements and thermostats, and its still going strong. When i drained it in 2013 to do the elements etc. I opened the drain valve and nothing came out, I eventually un hooked it and walked it to the door (its in my utility room) and applied water pressure via a garden hose screwed to the input, unscrewed the entire drain valve and jabbed at it with a screw driver till a trickle and then more came out. I flushed about a 5 gallon bucket full of lime and scale out of it. I swore i would drain it every year from then on.... and haven't drained it again in the next 7 years. It is 15 years old now and heats great... if it makes it one more year it will be someone else's problem.

When we bought this house it had a 9y/o 55gal HWH tank in the attic. That was an accident waiting to happen so I had it replaced with a tankless. I'm supposed to flush it(I have the kit) once a year but its been more like every 3 years.

I have the same thing with one of mine. The first time I flushed it I got water everywhere because I had to keep breaking up the pebbles of junk. The next couple of flushes it was fine. I skipped a couple of years and when I flushed it about a month ago, it was full of crap again. Mean while, the heater for the other side of the house never has a buildup of crap in it.

I changed out the drain valve on my water heater today. After changing an element 2 weeks ago and taking forever to drain, I thought it would help bunches. I was correct. I flushed it after installing the new drain valve easily and plan on flushing every 6 months. It was an easy install and did not cost very much in parts. Will be much easier and faster in the future. I took the handle off and wired it to the PRV so it would not get turned on accidently