Is It Safe to Add Yeast to a Septic System?

The bacteria in a septic system work in an airless environment and do quite well at breaking down solid matter from humans. The worst thing one can do is pour grease down the drain as it will form a barrier that eventually coats the lines. Dishwashers create another problem by making the liquid in the septic tank too alkaline. I'm using a system that has never needed pumping in 20 years because I don't use a dishwasher and greasy pans are well wiped with paper towels before the pans go in the water.

Yeast is much better than Ridex. The man who pumps my septic tank every other year says Ridex often just ends up solidified in the bottom of the tank. Make a septic tank cocktail with yeast and sugar and flush it down!