Our house has a "Craftmaster" gas water heater (c 2000), which acts like
it has a broken dip tube - the hot water is lukewarm, even though the
gas does come on from time to time.

I removed the inlet pipe. I can see (and feel) what seems to be a black
plastic hose extending down from the inlet nipple. It doesn't feel at
all free.

1. Do I need to remove the (galvanized) inlet nipple to get the tube
out?

2. Inside the tube, there was a plastic strip, about 4" long, with two
magnets in it. It was a snug fit, but it pulled out without excessive
force. What is this?

TIA,
George