For a septic with 2 tanks and a pump tank, which tanks should be pumped out?
June 2nd, 2009 | 
Author: I recently had my septic Tank Pumped out. The pump tank and the the tank where the house drain enters were pumped. When I aske why the second tank was not pumped I was told there was no need. The second tank was overflow for the water which emptied into the pump tank. Is this true or should all three have been pumpedout?
This is true. If you a have a sand mound, the last tank is the dosing tank. Effluent is pumped from this tank to the septic field. The first tank in the series collects all of the solid waste products. These settle to the bottom over time. There is a baffle that allows the water at the top of the tank to pour over into the second compartment. It prevents solids from transferring there.
If you have a gravity system, it is basically the same principle.
Posted in Tank Pump
This is true. If you a have a sand mound, the last tank is the dosing tank. Effluent is pumped from this tank to the septic field. The first tank in the series collects all of the solid waste products. These settle to the bottom over time. There is a baffle that allows the water at the top of the tank to pour over into the second compartment. It prevents solids from transferring there.
If you have a gravity system, it is basically the same principle.
References :
It really depends on your system and how it is loaded. My system has three tanks. Usually the second one needs to be pumped the most but on occasions I have had to pump all three. If there is a heavy load, like a lot of guests at Christmas with laundry, the flow rate can be too high and solids are carried to places they usually aren't.
We are required to have our system checked three times a year by a certified technician. They tell us which if any of the tanks needs pumping.
Usually the pump tank is the one with the least need to be pumped. I've only pumped our pump tank once in ten years.
References :