Jonathan Kamens wrote:
Matt writes:

* Your hot water will get used up more quickly if there are
periods of the day when you're using a lot of hot water.
(snip)
We've got a 40-gallon tank. I'm hoping that it wears out and we have
to replace it before two of my four kids get old enough to decide they
need to shower every morning like I do :-).

Very true. The teens in my house used to shower till the water
temperture drops regardless of what temperture I set for the tank. Now I
have a 12 minutes rule, I'll bang on the bathroom door and if they
ignore the warning then I'll head to the basement and shut the tank
inlet valve. Cold water showering are not subject to the 12 minutes rule.

FC