Every one of my many flushes has been somehow different. We dislodge different stones each time. The stones also have their own little history, i.e. what bugs they have in them, how old they are etc.
The Epsom Salt helps to move things out better than anything. But as you say you did things a little differently the second time, your results where a little different too. As long as you are successful in removing toxic old matter you are winning, I think. :-) Giz.