We use our own filtered and softened well water in the 5er. Thus, we have never had any serious crud in the HW tank. However, I do occasionally (like every couple of years or so) remove the nylon bushing and insert a tank flusher tube on the end of a garden hose, just to be sure. Have never had much of anything cruddy come out. But just for routine tank drains, like winterizing, I just open the T valve and let it out, then leave the valve cracked open slightly for the winter.
2003 Ford F-350 V-10 Crew Cab 4WD Long Bed
2004 Jayco Designer Medallion 29 RLTS 5th wheel
Bill, Gayle, and Mindi (dachshund)
Retired at last !
Nothing is foolproof to a sufficiently talented fool.