The main reason to have the tank pumped is not to remove the human solid waste, but to remove the waxes that float to the top of the tank. This wax build up consists of soap and fats that separate from the human waste. The waste itself isn't the problem because it falls to the bottom as sludge. The wax layer builds up on the top of the tank and at a certain point, this will become so thick that it will eventually work its way into the leach field lines and clog them. When this happens, it is going to cost a lot to replace the leach field itself. When you use products such as Rid X, they tend to break down the wax and help to move it along the system. You are better off to pump the system more often and not use any "enhancements". The number of people in the home is only one variable, how the system is used is also important. Where does the washing machine water go, is the water soft or hard, how many showers a day, garbage disposal usage, how you handle fats, such as bacon, etc. We put all fats into a empty soup can that is kept in the freezer and when it is 3/4 full it goes out in the garbage. Anything that you cook that has residual fats, such as bacon or hamburger, drain into the can while it is still liquid to dispose of it. We also use a lot of ammonia to break down grease so it doesn't build up in the drain pipes. It will separate again and become part of the fat layer in the septic tank later on, so the ammonia doesn't create a problem in the tank. When you compare the cost of a new septic system to the cost of pumping, every other year is cheap insurance. This is even more important where the soils have a high concentration of clay. If you have a backhoe, go to an area near your leach field and do a test perk test to see how good your drainage actually is. You might be surprised as to what you will learn.
