Hello:

Have the typical cylindrical type of upright gas fired hot water heater.
Probably about 5 yrs old, or so.

Lately, it is taking an inordinate amount of time to heat water up.
It used to be fairly quick; now my wife complains that
it takes "forever".

Heard about draining the crud via the valve at the bottom; the theory being
apparently
that the crud is acting as a thermal barrier for the heat. Likely ?

Frankly, have never played with the valve or draining the tank.

Is it likely that over the years a layer of crud, or whatever has built up
in the tank, and this is the cause of the slow heating ?

If so, woulds draining the tank likely help ?
Guess I'm wondering if the crud, if that is actually the problem, is
hard-baked on the inside,
or somehow loose enough such that draining the tank would help ?

How do I do this ? Do I flush it by letting the water run thru and out a
hose to the outside, or... ?

Any thoughts or comments would be most appreciated.

Thanks,
Bob