I had a spare dishwasher at one time, it came from a building refurb job, and I installed it in my cellar, it was very, very useful, for final cleaning of engine parts, cylinder heads for instance,, items came out so much cleaner than hand washing, de-greaser, paraffin, etc, can achieve, I don't remember using dish wash tablets, but I must have, because when taking a head out of the washer, the iron parts are already coated in extremely light red corrosion, (drying in a hot, steamy and maybe salty atmosphere) nothing that a wipe of oily cloth wont solve, but annoying none the less, there is of course salt in the tablets to give your wine glasses the sparkle that you desire, I am sure I ran it without tablets and without slat in the pot (for water softening), but eventually it packed up and was scrapped, fun while it lasted. I now have an air powered industrial degreaser which was donated from a pal who does automatic transmissions, when he bought out a competitor and found it surplus, it is a marvellous machine and "pickles" the components without the use of any abrasive material at all, but lack of space means it is "to one side" and when needed is a chore to re-commission, and while it is doing its job which is best left for hours, the compressor is running continuously (Hydrovane) that is annoying as well.
CLEM