Since solids will continue to build up at the bottom of the tank, it is imperative that the “septic tank be pumped out periodically.” Remember, sludge is not biodegradable if it’s
not pumped out, sludge will accumulate until it overflows.
The frequency of pumping out will depend primarily on the amount of wastewater that goes through the system each day. The frequency also depends on how careful you are about not throwing excess fats, rinds and other similar garbage down the drains. The more solid waste thrown in the system, the quicker the tank will fill up. Heavy flows of water also tend to make the tank fill up more quickly. That is why it is best not to use a garbage disposal in the system when you have a septic tank, and why water should not be left running indiscriminately in sinks or toilets.