You mean detergent right?
Apologies for the youtube link but this guy fits in nicely with the lemmy crowd and made a 40min video about optimal use of dishwashers and detergent. He does promote a specific powder detergent... but its from a good company ๐๐๐ and backed with science.
https://m.youtube.com/watch?v=DAX2_mPr9W8&pp=ygUhdGVjaG5vbG9neSBjb25uZWN0aW9ucyBkaXNod2FzaGVy