Cat Litter Clogging Toilet?
You can still flush it just change cat litter they make one that is wheat based and will wash away it,s called swheat scoop. If you look at http://www.septicdrain.com they have more info like that.
Rid-Ex Alternative for Your Septic Tank
The yeast and buttermilk are just eaten by the tank. But the baking soda does help to make the ph more to the liking of bacteria growth. unless your system has clogged before the bacteria that comes from your body is enough.