Household wastewater first flows into the septic tank, where it should stay for at least a day. In the tank, heavy solids in the wastewater settle to the bottom, forming a sludge layer, while grease and light solids float to the top forming a layer of scum.
The sludge and scum remain in the tank where naturally occurring bacteria work to break them down. The bacteria cannot completely break down all of the sludge and scum, however, and this is why septic tanks need to be pumped periodically. The separated wastewater in the middle layer of the tank is pushed out into the drain field as more wastewater enters the septic tank from the house. If too much water is flushed into the septic tank in a short period, the wastewater flows out of the tank before it has had time to separate. This can happen on days when water use is unusually high (laundry day, for example), or more often if the septic tank is too small for the household's needs.
Wipes!!!! Even if it says flushable, they are not! And one of the major components of failing systems.
Medicine. Changes the biological breakdown in the septic tank that is needed.
Feminine products. Use the garbage
Oil or grease from cooking. Wipe pots and pans before washing.
Beware of additives for septic tanks. Your septic tank should be pumped every 3 – 7 years, depending on usage. Your septic drain field is only for the liquids that naturally separate from the solids. If you break down the solids in the tank to go into your drain field, you could kill the drain field! Replacement is expensive.
If you have a garbage disposal, you will need to pump your system more often than without one.
So…. Remember the 3 P's What can go into a septic tank? Pee Poop Paper
Just because you can flush it, doesn’t mean you should.