[justlurking]

The best way to extend the lifetime of a tank water heater is to flush it regularly. I did so a few times a year, and the plumber said I probably added 5 years to the life.

If you are already at 25 years, you have been on borrowed time for 15 years. Tank heaters have an expected 10-year lifetime.

You should replace it as soon as possible. Depending on where it is installed, a failure due to corrosion can cause a great deal of damage. Drain pans don't always work properly.

It's not cheap, but a tankless heater is the way to go. It will cost about twice as much (installed), but they have a 20-year lifetime. You'll have an infinite amount of hot water (subject to the maximum flow rate and temperature boost it will support), and you won't be paying to keep water hot when you aren't using it.

[bert]

I have a long clear vinyl hose on the drain and a nozzle with a valve and section of copper tubing. I drag it all over the house to water the plants.

The plants get watered
the sediments get drained